问答题A jar contains 30 coins, of which 20 are nickels and 10 are dimes. If 7 coins are removed, how many nickels are left?  (1) More nickels are removed than dimes.  (2) The remaining coins in the jar are worth $1.55.

题目
问答题
A jar contains 30 coins, of which 20 are nickels and 10 are dimes. If 7 coins are removed, how many nickels are left?  (1) More nickels are removed than dimes.  (2) The remaining coins in the jar are worth $1.55.

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  • 第1题:

    18 of the EU members have replaced their national currencies by Euro notes and coins ()2002.

    A. for

    B. at

    C. since


    参考答案:C

  • 第2题:

    Given:Which is true?()

    A.If line 10 is removed, the compilation succeeds.

    B.If line 11 is removed, the compilation succeeds.

    C.If line 12 is removed, the compilation succeeds.

    D.If line 13 is removed, the compilation succeeds.

    E.More than one line must be removed for compilation to succeed.


    参考答案:C

  • 第3题:

    【T1】

    A.TO OBTAIN

    B.MADE OF

    C.IS WORTH A.IT IS CHEAPER【T1】______SILVER

    B.THE COINS WERE ACTUALLY【T2】______SILVER

    C.THE SILVER IN COINS【T3】______MUCH MORE LESS THAN 40 YEARS AGO IN THE UNITED STATES, IT WAS COMMON TO CHANGE A ONE-DOLLAR BILL FOR A DOLLAR"S WORTH OF SILVER.THAT IS BECAUSE【T4】______.BUT THOSE DAYS ARE GON

    E.THERE IS NO SILVER IN TODAY"S COINS.WHEN THE PRICE OF THE PRECIOUS METAL RISES ABOVE ITS FACE VALUE AS MONEY, THE METAL WILL BECOME MORE VALUABLE IN OTHER USES.SILVER COINS ARE NO LONGER IN CIRCULATION BECAUSE【T5】______THAN THEIR FACE VALU

    E.A SILVER FIRM COULD FIND THAT【T6】______BY MELTING DOWN COINS THAN BY BUYING IT ON THE COMMODITY MARKETS.COINS TODAY ARE MADE OF AN ALLOY OF CHEAPER METALS.


    正确答案:toobtain
    it为形式主语,不定式为真正主语,所以选toobtain。

  • 第4题:

    【T3】

    A.TO OBTAIN

    B.MADE OF

    C.IS WORTH A.IT IS CHEAPER【T1】______SILVER

    B.THE COINS WERE ACTUALLY【T2】______SILVER

    C.THE SILVER IN COINS【T3】______MUCH MORE LESS THAN 40 YEARS AGO IN THE UNITED STATES, IT WAS COMMON TO CHANGE A ONE-DOLLAR BILL FOR A DOLLAR"S WORTH OF SILVER.THAT IS BECAUSE【T4】______.BUT THOSE DAYS ARE GON

    E.THERE IS NO SILVER IN TODAY"S COINS.WHEN THE PRICE OF THE PRECIOUS METAL RISES ABOVE ITS FACE VALUE AS MONEY, THE METAL WILL BECOME MORE VALUABLE IN OTHER USES.SILVER COINS ARE NO LONGER IN CIRCULATION BECAUSE【T5】______THAN THEIR FACE VALU

    E.A SILVER FIRM COULD FIND THAT【T6】______BY MELTING DOWN COINS THAN BY BUYING IT ON THE COMMODITY MARKETS.COINS TODAY ARE MADE OF AN ALLOY OF CHEAPER METALS.


    正确答案:isworth
    句子缺谓语,C项意为“硬币中银的价值比面值多很多”,所以选isworth。

  • 第5题:

    How are hardware errors removed from an error report that are more than 30 days old?()

    • A、 /usr/bin/errpt -d H 30
    • B、 /usr/sbin/errclear - J H 30
    • C、 /usr/bin/errclear -d H 30
    • D、 /usr/sbin/errclear -j H 30

    正确答案:C

  • 第6题:

    单选题
    Given the fully-qualified class names:  com.foo.bar.Dog  com.foo.bar.blatz.Book  com.bar.Car  com.bar.blatz.Sun  Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JYM?()
    A

     Jar A

    B

     Jar B

    C

     Jar C

    D

     Jar D

    E

     Jar E


    正确答案: B
    解析: 暂无解析

  • 第7题:

    单选题
    A jar contains 10 blue, 8 green, and 6 red marbles. Every time a marble is removed from the jar, it is not replaced. What is the probability, to the nearest hundredth, that the second marble chosen is green if the first marble chosen is green?
    A

    0.28

    B

    0.29

    C

    0.30

    D

    0.31

    E

    0. 32


    正确答案: C
    解析:
    Because the first marble drawn is green that means there are a total of 23 marbles remaining. Seven of these are green. P (second green) = 7/23= 0.30

  • 第8题:

    单选题
    Phil has x quarters, y dimes, and z nickels and nothing else. Which of the following expressions represents the amount of money that Phil has, in dollars?
    A

    0.25x + 0.10y + 0.05z

    B

    2.5x + 1. 0y + 0.5z

    C

    25x + 10y + 5z

    D

    0.25x + 0.10y + 0.5z

    E

    25x + 10y + 50z


    正确答案: B
    解析:
    Multiply the value of each coin by the number of coins and add. 0.25x + 0.10y + 0.05z.

  • 第9题:

    单选题
    Which of the following statements is TRUE? ______.
    A

    Credit cards have more advantages than travellers’ cheques.

    B

    Dollar bills are as convenient as credit cards.

    C

    One-cent coins have been withdrawn from circulation.

    D

    You can increase your credit limit as you like.


    正确答案: A
    解析:
    B“现金会比信用卡好用”、C “一美分硬币已经不流通”与文中意思相矛盾,D.“你可以随意增加信用卡额度”在原文中没提到。由文章最后一段第一句话“Credit cards can be even more valuable than travellers’ cheques… (信用卡比旅行支票更有价值)”,可知信用卡比旅行支票更具价值,这与A项表述一致。

  • 第10题:

    单选题
    A

    They tried to collect more money than the ruler asked for.

    B

    They were given some silver and gold coins by the ruler.

    C

    They were excused from paying income tax.

    D

    They enjoyed being invited to dinner at the ruler’s palace.


    正确答案: C
    解析:
    细节题。录音提到“Of course the tax collector managed to collect more money than he paid to the ruler”,可知应选A项。
    【录音原文】
      A friend of mine told me that when he was a young man, he went to work as a teacher in one of the states of India. One day he received an invitation to dinner at the ruler’s palace. Very pleased, he went to tell his colleagues. They laughed and told him the meaning of the invitation. They had all been invited and each person who was invited has to bring with him a certain number of silver and gold coins. The number of coins varied according to the person’s position in the service of the government. My friend’s income was not high, so he did not have much to pay. Each person bound before the ruler, his gold went onto one heap, his silver went onto another heap, and in this way he paid his income tax for the year. This was a simple way of collecting income tax. The tax on property was also collected simply: The ruler gave a man the power to collect a tax from each owner of land or property in a certain area if this man promised to pay the ruler a certain amount of money. Of course the tax collector managed to collect more money than he paid to the ruler. The difference between the sum of money he collected and the sum of money he gave to the ruler was his profit.
    Questions 1 to 3 are based on the passage you have just heard.
    1. What do we know about the speaker’s friend?
    2. What was the real purpose of the ruler’s invitation?
    3. What does the passage say about the tax collectors?

  • 第11题:

    单选题
    Three fair coins are tossed at the same time. What is the probability that all three coins will come up heads or all will come up tails?
    A

    1/8

    B

    1/6

    C

    1/4

    D

    1/3

    E

    3/8


    正确答案: E
    解析:
    If three fair coins are tossed at the same time, the probability that all three will come up heads is (1/2)×(1/2)×(1/2) or 1/8. probability that all three coins will come up tails is also (1/2) × (1/2) × (1/2) or 1/8. Hence, the probability that all three coins will come up heads or all will come up tails is (1/8)+(1/8) or 1/4.

  • 第12题:

    单选题
    How are hardware errors removed from an error report that are more than 30 days old?()
    A

     /usr/bin/errpt -d H 30

    B

     /usr/sbin/errclear - J H 30

    C

     /usr/bin/errclear -d H 30

    D

     /usr/sbin/errclear -j H 30


    正确答案: A
    解析: 暂无解析

  • 第13题:

    Click the Exhibit button. Given the fully-qualified class names: com.foo.bar.Dog com.foo.bar.blatz.Book com.bar.Car com.bar.blatz.Sun Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JVM? ()

    A.Jar A

    B.Jar B

    C.Jar C

    D.Jar D

    E.Jar E


    参考答案:A

  • 第14题:

    使用VC6打开考生文件夹下的工程test36_1,此工程包含一个源程序文件test36_1.cpp,但该程序运行有问题,请改正函数中的错误,使该程序的输出结果为:

    2

    源程序文件test36_1.cpp清单如下:

    include<iostream.h>

    class amount;

    class coins

    {

    /***************** found *****************/

    enum units {penny, nickel, dime, quarter, half_dollar}

    /***************** found *****************/

    class amount;

    };

    class amount

    {

    /***************** found *****************/

    coins:units money;

    public:

    void setm();

    int germ();

    };

    void amount::setm()

    {

    money = coins::dime;

    }

    int amount::getm()

    {

    return money;

    }

    int main ( )

    {

    amount ob;

    ob.setm();

    cout << ob.getm()<<end1;

    return 0;

    }


    正确答案:(1) 错误;enum units{pennynickeldimequarterhalf_dollar} 正确:enum units {pennynickeldimequarterhalf_dollar}; (2) 错误:class amount; 正确:friend class amount; (3) 错误:coins:units money; 正确:coins::units money;
    (1) 错误;enum units{penny,nickel,dime,quarter,half_dollar} 正确:enum units {penny,nickel,dime,quarter,half_dollar}; (2) 错误:class amount; 正确:friend class amount; (3) 错误:coins:units money; 正确:coins::units money; 解析:(1)enum是枚举类型,units是本题中该类型的一个变量,后面为枚举表,大括号中为枚举符,枚举变量的值实际上是一个有名字的常量,所以它的定义结束时也需要一个分号;
    (2)类amount是类coins中定义的成员,要是想要访问coins类中的私有成员,把amount定义成普通的数据成员是不能做到的,只能把它定义成友元类,即可以访问coins类中的所有成员(提示:units是使用的默认定义,即私有成员);
    (3)units是类coins中的成员,在它的友元类中访问它时应该使用作用域符“::”,本题的错误是使用了冒号。

  • 第15题:

    【T2】

    A.TO OBTAIN

    B.MADE OF

    C.IS WORTH A.IT IS CHEAPER【T1】______SILVER

    B.THE COINS WERE ACTUALLY【T2】______SILVER

    C.THE SILVER IN COINS【T3】______MUCH MORE LESS THAN 40 YEARS AGO IN THE UNITED STATES, IT WAS COMMON TO CHANGE A ONE-DOLLAR BILL FOR A DOLLAR"S WORTH OF SILVER.THAT IS BECAUSE【T4】______.BUT THOSE DAYS ARE GON

    E.THERE IS NO SILVER IN TODAY"S COINS.WHEN THE PRICE OF THE PRECIOUS METAL RISES ABOVE ITS FACE VALUE AS MONEY, THE METAL WILL BECOME MORE VALUABLE IN OTHER USES.SILVER COINS ARE NO LONGER IN CIRCULATION BECAUSE【T5】______THAN THEIR FACE VALU

    E.A SILVER FIRM COULD FIND THAT【T6】______BY MELTING DOWN COINS THAN BY BUYING IT ON THE COMMODITY MARKETS.COINS TODAY ARE MADE OF AN ALLOY OF CHEAPER METALS.


    正确答案:madeof
    bemadeof为固定短语,意为“由……所组成,由……造成”,B项意为“硬币实际上是银制的”。

  • 第16题:

    阅读下列说明和C代码,回答问题 1 至问题 3,将解答写在答题纸的对应栏内。 【说明】 假币问题:有n枚硬币,其中有一枚是假币,己知假币的重量较轻。现只有一个天平,要求用尽量少的比较次数找出这枚假币。 【分析问题】 将n枚硬币分成相等的两部分: (1)当n为偶数时,将前后两部分,即 1...n/2和n/2+1...0,放在天平的两端,较轻的一端里有假币,继续在较轻的这部分硬币中用同样的方法找出假币: (2)当n为奇数时,将前后两部分,即1..(n -1)/2和(n+1)/2+1...0,放在天平的两端,较轻的一端里有假币,继续在较轻的这部分硬币中用同样的方法找出假币;若两端重量相等,则中间的硬币,即第 (n+1)/2枚硬币是假币。 【C代码】 下面是算法的C语言实现,其中: coins[]: 硬币数组 first,last:当前考虑的硬币数组中的第一个和最后一个下标 include <stdio.h> int getCounterfeitCoin(int coins[], int first,int last) { int firstSum = 0,lastSum = 0; int ì; If(first==last-1){ /*只剩两枚硬币*/ if(coins[first] < coins[last]) return first; return last; } if((last - first + 1) % 2 ==0){ /*偶数枚硬币*/ for(i = first;i <( 1 );i++){ firstSum+= coins[i]; } for(i=first + (last-first) / 2 + 1;i < last +1;i++){ lastSum += coins[i]; } if( 2 ){ Return getCounterfeitCoin(coins,first,first+(last-first)/2;) }else{ Return getCounterfeitCoin(coins,first+(last-first)/2+1,last;) } } else{ /*奇数枚硬币*/ For(i=first;i<first+(last-first)/2;i++){ firstSum+=coins[i]; } For(i=first+(last-first)/2+1;i<last+1;i++){ lastSum+=coins[i]; } If(firstSum<lastSum){ return getCounterfeitCoin(coins,first,first+(last-first)/2-1); }else if(firstSum>lastSum){ return getCounterfeitCoin(coins,first+(last-first)/2-1,last); }else{ Return( 3 ) } } }

    【问题一】 根据题干说明,填充C代码中的空(1)-(3) 【问题二】 根据题干说明和C代码,算法采用了( )设计策略。 函数getCounterfeitCoin的时间复杂度为( )(用O表示)。 【问题三】 若输入的硬币数为30,则最少的比较次数为( ),最多的比较次数为( )。


    正确答案:问题1
    (1)first+(last-first)/2 或(first+last)/2                 
    (2)firstSum<lastSum
    (3)first+(last-first)/2 或(first+last)/2
    问题2
    (4)分治法
    (5)O(nlogn)
    问题3
    (6)2     (7)4

  • 第17题:

    Given the fully-qualified class names:  com.foo.bar.Dog  com.foo.bar.blatz.Book  com.bar.Car  com.bar.blatz.Sun  Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JYM?() 

    • A、 Jar A
    • B、 Jar B
    • C、 Jar C
    • D、 Jar D
    • E、 Jar E

    正确答案:A

  • 第18题:

    单选题
    A jar contains 54 marbles each of which is blue, green, or white. The probability of selecting a blue marble at random from the jar is 1/3, and the probability of selecting a green marble at random is 4/9. How many white marbles does the jar contain?
    A

    6

    B

    8

    C

    9

    D

    12

    E

    18


    正确答案: A
    解析:
    Since the probability of selecting a blue marble at random from the jar is 1/3 and the probability of selecting a green marble at random from the jar is 4, the probability of selecting a white marble is 1-(1/3 + 4/9) = 1- (7/9) = 2/9. If x marbles of the 54 marbles in the jar are white, then x/54 = 2/9, 9x = 108, x = 108/9 = 12.

  • 第19题:

    填空题
    The ratio of men to women in a room is 4: 5. If the room contains three more women than men, how many women are in the room?____

    正确答案: 15
    解析:
    根据题干可假设,屋子里的男人有4x,女人有5x,又因为男人比女人多3,所以5x=4x+3,所以x = 3。所以屋子里有女人5(3)= 15人。

  • 第20题:

    单选题
    Which of the following is NOT the purpose of America’s central bank?
    A

    Controlling the flow of money in the economy.

    B

    Overseeing the activities of banks.

    C

    Producing and distributing bank notes and coins.

    D

    Contributing to the maintenance of a stable financial system.


    正确答案: B
    解析:
    特定信息的找寻和判断。关于美国中央银行的目标,录音中指出“Its purpose is to control the flow of money in the economy, to supervise banking activity and to protect the financial system”,表明其目标是控制货币流量,监督银行业活动,并且保护金融体系。分别对应选项A,B和D的内容,唯有C项(制造与发行纸币和硬币)未曾提及。
    【录音原文】
    America’s Central Bank is part of a larger financial system called the United States Federal Reserve System. It is not a single bank, but a banking system with operations that are both public and private. Its purpose is to control the flow of money in the economy, to supervise banking activity and to protect the financial system.

  • 第21题:

    单选题
    Given: Which is true?()
    A

    If line 10 is removed, the compilation succeeds.

    B

    If line 11 is removed, the compilation succeeds.

    C

    If line 12 is removed, the compilation succeeds.

    D

    If line 13 is removed, the compilation succeeds.

    E

    More than one line must be removed for compilation to succeed.


    正确答案: E
    解析: 暂无解析

  • 第22题:

    单选题
    In a wallet containing nickels and dimes, the ratio of nickels to dimes is 2:5. If there are 42 coins in all, what is the value of the dimes?
    A

    $1. 20

    B

    $3. 00

    C

    $1. 50

    D

    75€

    E

    30€


    正确答案: D
    解析:
    Let 2x the number of nickels and 5x the number of dimes, then 2x+5x=42, so x=6. There are 30 dimes, worth $3.00.

  • 第23题:

    单选题
    Three coins are tossed at the same time. What is the probability that exactly two heads are face up?
    A

    1/8

    B

    1/4

    C

    3/8

    D

    1/2

    E

    5/8


    正确答案: B
    解析:
    First, list all the possible outcomes when three coins are tossed in the air. When a coin is tossed, there are two outcomes, Heads or Tails. When three coins are tossed, there are 2×2×2= 8 possible outcomes:
    {HHH, HHT, HTH, THH, HTI', THT, TTH, TIT} Three of these outcomes have exactly two heads. Therefore, P (exactly two heads) =3/8.