A computer is a machine designed to perform work mathematically and to store and select information that has been fed into it. I

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问题     A computer is a machine designed to perform work mathematically and to store and select information that has been fed into it. It is run by either mechanical or electronic means. These machines can do a great deal of complicated work in a very short time. A large computer, for example, can add or subtract nine thousand times a second, multiply a thousand times a second, or divide five hundred times a second. Its percentage of error is about one in a billion digits. It has been estimated that human beings making calculations average about one mistake per two hundred digits.
    The heart of an electronic computer lies in its vacuum tubes, or transistors. Its electronic circuits work a thousand times faster than the nerve cells in the human brain. A problem that might take a human being two years to solve can be solved by a computer in one minute, but in order to work properly, a computer must be given instructions—it must be programmed.
    Computers can be designed for many specialized purposes, they can be used to prepare payrolls , guide airplane flights, direct traffic, even to play chess. Computers play an essential role in modern automation in many plants and factories throughout the world.
Computers are valuable to industry because they______.

选项 A、can solve all mathematical problems
B、perform rapidly
C、eliminate mathematical errors from calculations
D、detect errors in human calculations quickly

答案B

解析 文中第一段第三句说:“这些机器能够在极短的时间内处理大量的复杂工作。”文中第二段第三句说: “一个也许需要花费一个人两年时间才能解决的问题,而靠计算机只要一分钟就可以……”结合文中提供的其他信息,我们可以推断出正确答案为B。此题用排除法也可以找到答案。选项A、C、D在文中未涉及,均可排除,只有选项B是文章中所论述的内容。
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