Questions 21 to 25 are based on the following passage.Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean
题目
Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. How did scientists discover the source of lead pollution in Greenland? （）
- A、By analyzing the data published in journals like Nature and Ambio.
- B、By observing the lead accumulations in different parts of the arctic area.
- C、By studying the chemical elements of soil and snow in Northeastern America.
- D、By comparing the chemical compositions of leaded gasoline used in various countries.
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更多“Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Cle”相关问题
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第1题：
In the 1960s, many young Americans were dissatisfied with American society. They wanted to end the Vietnam War and to make all of the people in the U.S. equal. Some of them decided to "drop out" of American society and form their own societies . They formed utopian communities , which they called "communes," where they could follow their philosophy of "do your own thing." A group of artists founded a commune in southern Colorado called "Drop City." Following the ideas of philosopher and architect Buckminster Fuller they built domeshaped houses from pieces of old cars. Other groups, such as author Ken Kesey's Merry Pranksters, the followers fo San Francisco poet Steve Gakin, and a group that called itself the Hog Farm, lived in old school huses and traveled around the United States. The Hog Farm become famous when they helped organize the Woodstock Rock Festival in 1969. Steve Gaskin's followers tried to settle down on a farm in Tennessee, but they had to leave when some members of the gruop were arrested for growing marijuana.
Not all communes believed in the philosophy of "do you own thing," however . Twin Oaks , a commune founded in Virgiania in the late 1960s, was based on the ideas of psychologist B.F.Skinner. The people who lived at Twin Oaks were carefully controlled by Skinner's "conditioning" techniques to do things that were good for the community. In 1972, Italian architect Paolo Soleri began to build Arcosanti, a utopian city Arizsona where 2500 people will live closely together in one large building called an "archology" Soleri believes that people must live closely together so that they will all become one.
What was the Twin Oaks commune base on ?a.The philosophy of "do your own thing"
b.Virginaia in the late 1960s
c.The ideas of psychologist
d.The belief that people must live closely togerher.答案：C解析： -
第2题：
共用题干
New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes（维度）of the Earth,where ice is more common , absorbs more of the sun's energy and warmth than an icy,white background. Dark-colored black carbon,or soot, absorbs sunlight,while lighter colored ice reflects sunlight.
Soot in areas with snow and ice may play an important role in climate change.Also,if snow and ice covered areas begin melting,the warming effect increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.
Hansen found soot's effect on snow albedo（反照率）,which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.
“Black carbon reduces the amount of energy reflected by snow back into space,thus heating the snow surface more than if there were no black carbon,”Hansen said. Soot's increased absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.
Hansen cautioned,although the role of soot in altering global climate is substantial,it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century .Such gases are expected to be the largest climate forcing for the rest of the century.
The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.What is the main cause of climate warming during the past century?
A: Soot.
B: Snow.
C: Greenhouse gases.
D:.Wind.答案：C解析：文章第二段最后一句“…while lighter colored ice reflects sunlight.”说浅色的冰反射太阳光，而黑色的煤烟灰并不反射。其他三项在文章一、二段都有提到，故本题选C。
根据第五段首句“Black carbon reduces the amount of energy reflected by snow back in-to space, thus heating the snow surface more than if there were no black carbon,”可知，黑炭覆盖的地区有更强烈的加热效果。故本题选B。
第五段中的“This forcing”指的是其前面所说的“Soot's increased absorption of solar energy”。因此本题选B。
根据第六段“…it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century.”可知，温室气体是上世纪气候变暖的首要原因，故选C。
由最后一段最后一句“…which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.”知，部分大规模的温室效应发生在有厚雪覆盖层和阳光强烈的地方。故本题选C。 -
第3题：
共用题干
New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes（维度）of the Earth,where ice is more common , absorbs more of the sun's energy and warmth than an icy,white background. Dark-colored black carbon,or soot, absorbs sunlight,while lighter colored ice reflects sunlight.
Soot in areas with snow and ice may play an important role in climate change.Also,if snow and ice covered areas begin melting,the warming effect increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.
Hansen found soot's effect on snow albedo（反照率）,which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.
“Black carbon reduces the amount of energy reflected by snow back into space,thus heating the snow surface more than if there were no black carbon,”Hansen said. Soot's increased absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.
Hansen cautioned,although the role of soot in altering global climate is substantial,it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century .Such gases are expected to be the largest climate forcing for the rest of the century.
The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.Which of the following statements of soot is NOT true?
A: It absorbs sun's heat.
B: It is responsible for climate change.
C: It reflects sunlight.
D:.It may account for a quarter of global warming over the past century.答案：C解析：文章第二段最后一句“…while lighter colored ice reflects sunlight.”说浅色的冰反射太阳光，而黑色的煤烟灰并不反射。其他三项在文章一、二段都有提到，故本题选C。
根据第五段首句“Black carbon reduces the amount of energy reflected by snow back in-to space, thus heating the snow surface more than if there were no black carbon,”可知，黑炭覆盖的地区有更强烈的加热效果。故本题选B。
第五段中的“This forcing”指的是其前面所说的“Soot's increased absorption of solar energy”。因此本题选B。
根据第六段“…it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century.”可知，温室气体是上世纪气候变暖的首要原因，故选C。
由最后一段最后一句“…which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.”知，部分大规模的温室效应发生在有厚雪覆盖层和阳光强烈的地方。故本题选C。 -
第4题：
根据以下材料，回答
The American Revolution was not arevolution in the sense of a radical or total change. It was not a sudden andviolent overturning of the political and social framework, such as lateroccurred in France and Russia, when both were already independent nations.Significant changes were ushered in, but they were not breathtaking. Whathappened was accelerated evolution rather than outright revolution. During theconflict itself people went on working and praying, marrying and playing. Mostof them were not seriously disturbed by the actual fighting, and many of themore isolated communities scarcely knew that a war was on.
America′s War of Independence heralded thebirth of three modem nations. One was Canada, which received its first largeinflux of English-speaking population from the thousands of loyalists who fledthere from the United States. Another was Australia, which became a penalcolony now that America was no longer available for prisoners and debtors. Thethird new comer--the United States--based itself squarely on republican principles.
Yet even the political overturn was not asrevolutionary as one might suppose. In some states, notable Connecticut andRhode Island, the war largely ratified a colonial self-rule alreadyexisting.British officials, everywhere ousted, were replaced by a home-growngoverning class, which promptly sought a local substitute for king andParliament.
Which of the following would be thebest title for the passage?A.The United States: An Isolated Community
B.Surprising Events During the AmericanRevolution
C.Canada and the American War ofIndependence
D.The American Revolution: Evolution NotRevolution答案：D解析：主旨题。通读全文可知，文章的结构是总一分结构。第一段是总括段，第二、三段是分段。根据第一段中“The American Revolution was not a revolution in the sense of aradical or total change．”“Significant changes wereushered in，but they were not breathtaking．What happened was accelerated evolution rather than outrightrevolution．"可知美国革命并未导致完全的和彻底的变化，所发生的只是进化的加速，并不算是一场革命。所以D项“美国革命：进化而不是革命”作为文章标题最恰当。 -
第5题：
Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. The authors of the Ambio study have found that（）
- A、forests get rid of lead pollution faster than expected
- B、lead accumulations in forests are more difficult to deal with
- C、lead deposits are widely distributed in the forests of the US
- D、the upper layers of soil in forests are easily polluted by lead emissions
正确答案:A -
第6题：
Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. The study published in the journal Nature indicates that （）
- A、the Clean Air Act has not produced the desired results
- B、lead deposits in arctic snow are on the increase
- C、lead will stay in soil and snow longer than expected
- D、the US is the major source of lead pollution in arctic snow
正确答案:D -
第7题：
Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. How did scientists discover the source of lead pollution in Greenland? （）
- A、By analyzing the data published in journals like Nature and Ambio.
- B、By observing the lead accumulations in different parts of the arctic area.
- C、By studying the chemical elements of soil and snow in Northeastern America.
- D、By comparing the chemical compositions of leaded gasoline used in various countries.
正确答案:D -
第8题：
单选题According to the passage, a major difference between the colonization policy of the United States and that of Mexico in Texas in the 1800’s was the _____.Adegree to which policies were based on tradition
Bform of economic interdependency between different cultural groups
Ctreatment of the native inhabitants
Drelationship between the military and the settlers
正确答案： C解析：
根据第二段可知，美国和墨西哥对德克萨斯的殖民化的主要不同在于，墨西哥人和土著印第安人通婚，并吸收他们的文化。而美国却征服当地人。因此，主要区别是对待当地居民的态度不同。 -
第9题：
单选题According to the passage, which of the following is TRUE?AFreedman and his colleagues hired 400,000 Americans to collect data.
BAbout four hundred thousand Americans worked for Freedman's team full time for 13 years.
CPeople who took part in Freedman's research are about 50 to 70 years old.
DPeople who are 50 to 70 years old seldom drink coffee
正确答案： C解析： -
第10题：
单选题The expression “fared best” in the sentence “During the 1960s and 1970s, and again after 1992, the poorest groups fared best.” in para. 8 can be paraphrased by which of the following?Aobtained higher income
Blived a better life
Cenjoyed more equality
Dpaid lower income tax
正确答案： A解析：
题目问的是：第8段中的句子“在20世纪60年代到70年代期间，还有1992年以后的时期，最穷的群体进展最好”，里面的“fared best”可以用下列哪一项释义？从文中可知，这两段时期里贫富差距有所缩小，即使是穷人也过上了好日子，选项B意思相近。故选B。 -
第11题：
单选题Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. The authors of the Ambio study have found that（）Aforests get rid of lead pollution faster than expected
Blead accumulations in forests are more difficult to deal with
Clead deposits are widely distributed in the forests of the US
Dthe upper layers of soil in forests are easily polluted by lead emissions
正确答案： D解析： 暂无解析 -
第12题：
单选题NEWS BROADCAST 5 Questions 7 and 8 are based on the following news. At the end of the news item. you will be given 20 seconds to answer the questions. Now listen to the news.Which manufacturer’s sales dropped the most in percentage in June?AChrysler.
BDaimler Chrysler.
CGeneral Motors.
DFord.
正确答案： D解析： 事实细节题。关于6月份各汽车制造商销售额下降的情况，新闻中提到，通用汽车6月份销售额下降了18%，福特下降了29%，而克莱斯勒汽车下降了36%。可知A项正确。听录音时应重点捕捉数字百分比。 -
第13题：
In the 1960s, many young Americans were dissatisfied with American society. They wanted to end the Vietnam War and to make all of the people in the U.S. equal. Some of them decided to "drop out" of American society and form their own societies . They formed utopian communities , which they called "communes," where they could follow their philosophy of "do your own thing." A group of artists founded a commune in southern Colorado called "Drop City." Following the ideas of philosopher and architect Buckminster Fuller they built domeshaped houses from pieces of old cars. Other groups, such as author Ken Kesey's Merry Pranksters, the followers fo San Francisco poet Steve Gakin, and a group that called itself the Hog Farm, lived in old school huses and traveled around the United States. The Hog Farm become famous when they helped organize the Woodstock Rock Festival in 1969. Steve Gaskin's followers tried to settle down on a farm in Tennessee, but they had to leave when some members of the gruop were arrested for growing marijuana.
Not all communes believed in the philosophy of "do you own thing," however . Twin Oaks , a commune founded in Virgiania in the late 1960s, was based on the ideas of psychologist B.F.Skinner. The people who lived at Twin Oaks were carefully controlled by Skinner's "conditioning" techniques to do things that were good for the community. In 1972, Italian architect Paolo Soleri began to build Arcosanti, a utopian city Arizsona where 2500 people will live closely together in one large building called an "archology" Soleri believes that people must live closely together so that they will all become one.
Why did some young Americans decide to "drop out" of scoiety during the 1960s?a.They were not satisfied with American society.
b.They wanted to grow marijuana.
c.They wanted to go to the Vietnam War.
d.They did not want all people to be equal.答案：A解析： -
第14题：
共用题干
New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes（维度）of the Earth,where ice is more common , absorbs more of the sun's energy and warmth than an icy,white background. Dark-colored black carbon,or soot, absorbs sunlight,while lighter colored ice reflects sunlight.
Soot in areas with snow and ice may play an important role in climate change.Also,if snow and ice covered areas begin melting,the warming effect increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.
Hansen found soot's effect on snow albedo（反照率）,which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.
“Black carbon reduces the amount of energy reflected by snow back into space,thus heating the snow surface more than if there were no black carbon,”Hansen said. Soot's increased absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.
Hansen cautioned,although the role of soot in altering global climate is substantial,it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century .Such gases are expected to be the largest climate forcing for the rest of the century.
The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.“This forcing” in Paragraph 5 refers to_____.
A: sun's heating on snow surface
B: soot's increased absorption of solar energy
C: carbon-dioxide's warming effect
D: snow's increased reflection of sunlight答案：B解析：文章第二段最后一句“…while lighter colored ice reflects sunlight.”说浅色的冰反射太阳光，而黑色的煤烟灰并不反射。其他三项在文章一、二段都有提到，故本题选C。
根据第五段首句“Black carbon reduces the amount of energy reflected by snow back in-to space, thus heating the snow surface more than if there were no black carbon,”可知，黑炭覆盖的地区有更强烈的加热效果。故本题选B。
第五段中的“This forcing”指的是其前面所说的“Soot's increased absorption of solar energy”。因此本题选B。
根据第六段“…it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century.”可知，温室气体是上世纪气候变暖的首要原因，故选C。
由最后一段最后一句“…which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.”知，部分大规模的温室效应发生在有厚雪覆盖层和阳光强烈的地方。故本题选C。 -
第15题：
共用题干
New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes（维度）of the Earth,where ice is more common , absorbs more of the sun's energy and warmth than an icy,white background. Dark-colored black carbon,or soot, absorbs sunlight,while lighter colored ice reflects sunlight.
Soot in areas with snow and ice may play an important role in climate change.Also,if snow and ice covered areas begin melting,the warming effect increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.
Hansen found soot's effect on snow albedo（反照率）,which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.
“Black carbon reduces the amount of energy reflected by snow back into space,thus heating the snow surface more than if there were no black carbon,”Hansen said. Soot's increased absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.
Hansen cautioned,although the role of soot in altering global climate is substantial,it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century .Such gases are expected to be the largest climate forcing for the rest of the century.
The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.Which of the following areas shows a greater warming effect?
A: Ice sea areas.
B: Areas with black carbon.
C: Areas covered with white snow.
D: Melting glaciers.答案：B解析：文章第二段最后一句“…while lighter colored ice reflects sunlight.”说浅色的冰反射太阳光，而黑色的煤烟灰并不反射。其他三项在文章一、二段都有提到，故本题选C。
根据第五段首句“Black carbon reduces the amount of energy reflected by snow back in-to space, thus heating the snow surface more than if there were no black carbon,”可知，黑炭覆盖的地区有更强烈的加热效果。故本题选B。
第五段中的“This forcing”指的是其前面所说的“Soot's increased absorption of solar energy”。因此本题选B。
根据第六段“…it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century.”可知，温室气体是上世纪气候变暖的首要原因，故选C。
由最后一段最后一句“…which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.”知，部分大规模的温室效应发生在有厚雪覆盖层和阳光强烈的地方。故本题选C。 -
第16题：
根据以下材料，回答
The American Revolution was not arevolution in the sense of a radical or total change. It was not a sudden andviolent overturning of the political and social framework, such as lateroccurred in France and Russia, when both were already independent nations.Significant changes were ushered in, but they were not breathtaking. Whathappened was accelerated evolution rather than outright revolution. During theconflict itself people went on working and praying, marrying and playing. Mostof them were not seriously disturbed by the actual fighting, and many of themore isolated communities scarcely knew that a war was on.
America′s War of Independence heralded thebirth of three modem nations. One was Canada, which received its first largeinflux of English-speaking population from the thousands of loyalists who fledthere from the United States. Another was Australia, which became a penalcolony now that America was no longer available for prisoners and debtors. Thethird new comer--the United States--based itself squarely on republican principles.
Yet even the political overturn was not asrevolutionary as one might suppose. In some states, notable Connecticut andRhode Island, the war largely ratified a colonial self-rule alreadyexisting.British officials, everywhere ousted, were replaced by a home-growngoverning class, which promptly sought a local substitute for king andParliament.
What will the paragraph following thepassage most probably discuss?A.The transport of prisoners to Australia.
B.The creation of new state governments.
C.Events leading up to the AmericanRevolution.
D.How Canada and the United States becamefriends.答案：B解析：推断题。文章第二段讲的是美国独立战争宣布了三个现代国家的诞生：加拿大、澳大利亚、美国。第三段说的是美国创立的具体情况，并列举康涅狄格和罗德岛等州来举例说明。因此推断文章接下来最有可能谈论的是新州政府的成立。 -
第17题：
Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. It can be inferred from the last paragraph that scientists （）
- A、are puzzled by the mystery of forest pollution
- B、feel relieved by the use of unleaded gasoline
- C、still consider lead pollution a problem
- D、lack sufficient means to combat lead pollution
正确答案:C -
第18题：
The economy of the United states after 1952 was the econnomy of a well-fed,almost fully employed people. Despit occasional alarms, the country escaped any postwar depression and lived in a state of boom. A n economic survey of the year 1955, a typical year of the 1950’s, may be typical as illustrating the rapid economic growth of the decade. The national output was value at 10 percent above that of 1954 (1955 output was estimated at 392 billion dollars). The production of manufacturers was about 40 percent more than it had averaged in the years immediately following World War 2. The country’s business spent about 30billion dollars for new factories and machinery. National income available for spending was almost a third greater than it had been it had been in 1950. Consumers spent about 256 billion dollars; that is about 700 million dollars a day ,or about twenty-five million dollars every hour , all round the clock. Sixty-five million people held jobs and only a little more than two million wanted jobs but could not find them . Only agriculture complained that it was not sharing in the room. To some observers this was an ominous echo of the mid-1920’s . As farmer’s shre of their products declined , marketing costs rose. But there were , among the observers of the national economy, a few who were not as confident as the majority . Those few seemed to fear that the boom could not last and would eventually lead to the oppsite-depression. Which of the following were LEAST satisfied with the national economy in the 1950’s?（）
- A、Economists
- B、Frmaers
- C、Politicians
- D、Steelworkers
正确答案:B -
第19题：
Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. Lead accumulation worldwide decreased significantly after the use of unleaded gas in the US （）
- A、was discouraged
- B、was enforced by law
- C、was prohibited by law
- D、was introduced
正确答案:B -
第20题：
单选题Which of the following is TRUE?AIn the 1920s, women were limited to being teachers, nurses or office workers.
BWomen mainly paid their attention to how they were paid in the 1960s.
CWomen asked to change “all men are created equal” into “all human beings are created equal”.
DNo states have ever provided women with jobs in the government.
正确答案： A解析：
推理判断题。从文章的第四段第一句话The Women’s Liberation movement, which developed during the 1960s, has focused on economic rights such as ‘equal pay for equal work’ 可知，在20世纪60年代，美国妇女的权利运动主要集中在同工同酬方面，主要关注的是自己的经济地位。所以B项正确。A项错误，倒数第二段末句提到女性的职业主要有teachers, nurses or office workers，而不是在这几个职业上受到限制。C项错误，由末句可知，是妇女解放运动的领导认为all men are created equal的意思是所有人类平等，而不是只有男人平等。D项错误，由with jobs in the government.定位倒数第二段倒数第二句，可知只有很少的妇女在学术和政府方面担任高层。 -
第21题：
单选题The modern Internet, first established in the mid-1980s, is based on the technology developed for the ARPANET, it was created by the United States Department of Defense in the 1960s.AARPANET, it was created by the United States Department of Defense
BARPANET; it was created by the United States Department of Defense
CARPANET, which was created by the United States Department of Defense
DARPANET, being created by the United States Department of Defense
EARPANET; the United States Department of Defense created it
正确答案： E解析：
原句仅用一个逗号将两个独立的句子连接起来。B虽纠正了这个错误，但是不符合逻辑。E也使用了指代模糊的it。D不符合逻辑因为分词“being”将“the Internet”作为主语，是没有意义的。 -
第22题：
单选题For many years marine centrifuges were designed for （） operation, that is the machines were run for a period during which solids accumulated in the bowlThe machine was stopped when the accumulated solids began to impair its performance.Apurifying
Bbatch
Clong period
Dtemporary
正确答案： B解析： 暂无解析 -
第23题：
单选题NEWS BROADCAST 4 Questions 8 and 9 are based on the following news. At the end of the news item, you will be given 20 seconds to answer the questions. Now listen to the news. Top officials of several U. S. intelligence agencies believe thatAthe country’s security is not good enough.
Bthe U. S. will face an attempted terrorist threat.
Cthere will be no actual attack in the U.S.
Dan anti-terrorism practice will be held in the following months.
正确答案： A解析： 事实细节题。新闻开头提到，美国各情报局的首脑们在国家安全问题上持有一致看法。参议院的听证会表示，在未来3到6个月内美国必然会遭到企图恐怖分子的袭击。可知，选项B为正确答案。 -
第24题：
单选题Questions 21 to 25 are based on the following passage. Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly. A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining. In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States. In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline. Many scientists had believed that the lead would stay in soil and snow for a longer period. The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected. Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. The study published in the journal Nature indicates that （）Athe Clean Air Act has not produced the desired results
Blead deposits in arctic snow are on the increase
Clead will stay in soil and snow longer than expected
Dthe US is the major source of lead pollution in arctic snow
正确答案： B解析： 暂无解析