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问题 选择题

如图所示的电路，电源电压保持不变，闭合开关S，将滑动变阻器的滑片P向左移动过程中，下列说法正确的是（   ）

A．电流表的示数变大

B．电压表的示数变大

C．电压表与电流表示数的比值不变

D．电压表示数变大，电流表示数变小

答案

答案：C

本题涉及的知识是电路分析。由电路图可知，电阻R与滑动变阻器串联，电压测量R两端的电压，电流表测量电路中的电流。滑动变阻器的滑片P向左移动时，电阻增大，电流减小，R两端的电压减小。电压表与电流表示数的比值是R的电阻，保持不变。

单项选择题

Comparisons were drawn between the development of television in the 20th century and the diffusion of printing in the 15th and 16th centuries. Yet much had happened (91) . As was discussed before, it was not (92) the 19th century that the newspaper became the dominant pree-leetronie (93) , following in the wake of the pamphlet and the book and in the (94) of the periodical. It was during the same time that the communications revolution (95) up, beginning with transport, the railway, and leading (96) through the telegraph, the telephone, radio, and motion pictures (97) the 20th-eentury world of the motor ear and the airplane. Not everyone sees that process in (98) . It is important to do so.
It is generally recognized, (99) , that the introduction of the computer in the early 20th century, (100) by the invention of the integrated circuit during the 1960s, radically changed the process, (101) its impact on the media was not immediately (102) . As time went by, computers became smaller and more powerful, and they became "personal" too, as well as (103) , with display becoming sharper and storage (104) increasing. They were thought of, like people, (105) generations, with the distance between generations much (106)
It was within the computer age that the term" information society" began to be widely used to describe the (107) within which we now live. The communications revolution has (108) both work and leisure and how we think and feel both about place and time, but there have been (109) views about its economic, political, social and cultural implications. "Benefits" have been weighed (110) "harmful" outcomes. And generalizations have proved difficult.

A．between

B．before

C．since

D．later
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单项选择题

全国代表大会代表的名额及产生办法，由（）决定。

A.中央委员会

B.中央委员会常务委员会

C.中央委员会征求基层团委意见后
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