Today we do not measure the speed of computer functions in minutes, or in seconds, or even in hundredths(1 /100)or thousandths(1

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问题     Today we do not measure the speed of computer functions in minutes, or in seconds, or even in hundredths(1 /100)or thousandths(1/1000)of seconds. We measure the speed of computers in bil-lionths of seconds. We call one billionth of a second a nanosecond.
    Computers were not always so fast, of course. In fact, at one time, the human mind could perform calculations faster than a computer. Let us look briefly at the development of the computer. We will see that the Computer Revolution happened only when computers developed their incredible speed. In 1833, Charles Babbage built his "analytical engine", the first computing machine. His colleague, Augusta Ada, the Countess of Lovelace, continued Babbage’s work. She became the first programmer in history. Fifty years later, Herman Hollerith designed a machine that counted automatically. This machine was used to count the number of people in the United States for the 1890 census. It used a system of punch cards. Hollerith’s company, by the way, eventually became IBM(International Business Machines).
    The first large digital computer was built by IBM in 1944. It was called the Mark I. Then in 1947,IBM built the Mark II. Today we cannot imagine how slow these computers were, just as we cannot imagine how fast modern computers are. These computers needed one or two seconds to perform one calculation. In these same years, electronic computers developed. They were much faster than the huge, slow Mark I and Mark II. ENIAC is the name of the first all-electronic computer, built in 1944 and 1945. The world was amazed to learn the speed of this computer: 5 000 additions per second, and 300 multiplications per second. Today we smile at these "slow" speeds.
    Then in 1960 the real "revolution" began with the introduction of integrated circuits. Today, thousands of transistor circuits can fit on one small silicon chip. As a result, we now measure the speed of computers in nanoseconds.
The best title for this passage would be______.

选项 A、The Computer and the silicon chip
B、The Computer Revolution: Birth of the Nanosecond
C、Five Thousand Additions in One Second
D、IBM:International Business Machines Corporation

答案B

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