题目内容
曼彻斯特编码的效率是（47）％，4B/5B编码的效率是（48）％。 47（）
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个案研究中常用的研究方法主要有（ ）
In ancient times the most important examinations were spoken, not written. In the schools of ancient Greece and Rome, testing usually consisted of saying poetry aloud or giving speeches.In the European universities of the Middle Ages, students who were working for advanced degrees had to discuss questions in their field of study with people who had made a special study of the subject. This custom exists today as part of the process of testing candidates for the doctor’s degree.Generally, however, modern examinations are written. The written examination, where all students are tested on the same question, was probably not known until the nineteenth century. Perhaps it came into existence with the great increase in population and the development of modern industry. A room full of candidates for a state examination, timed exactly by electric clocks and carefully watched over by managers, resembles a group of workers at an automobile factory. Generally, during examinations teachers and students are expected to act like machines.One type of test is sometimes called an "objective" test. It is intended to deal with facts, not personal opinions. To make up an objective test the teacher writes a series of questions, each of which has only one correct answer. Along with each question the teacher writes the correct answer and also three statements that look like correct answers to students who have not learned the material properly. The main idea of paragraph 3 is that （）
Some people hold the mistaken belief that our domestic products are（）(总是次于进口商品)
There was a time when any personal information that was gathered about us was typed on a piece of paper and (36) ______ away in a file cabinet. It could remain there for years and, often (37) ______, never reach the outside world. Things have done a complete about-face since then. (38) ______ for the change has been the astonishingly (39) ______ development in recent years of the computer. Today, any data that is (40) ______ about us in one place or another- and for one reason or another - can be stored in a computer bank. It can then be easily passed to other computer banks. They are owned by (41) ______ and by private businesses and corporations, lending (42) ______, direct mailing and telemarketing firms, credit bureaus, credit card companies, and government (43) ______ at the local, state, and federal level. A growing number of Americans are seeing the accumulation and distribution of computerized data as a frightening invasion of their privacy. (44) ___ as the computer becomes increasingly efficient, easier to operate, and less costly to purchase and maintain. In 1970, a national survey showed that (45)_____. Seven years later, 47 percent expressed the same worry. (46)_____. 46（）
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