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问题 选择题

当你发现显微镜的镜头不清洁时，除去污垢的正确方法是（　　）

A．用纱布擦

B．用手擦

C．用擦镜纸擦

D．用纸巾擦

答案

通过分析知道当你发现显微镜镜头不清洁时，除去污物，是对显微镜的物镜和目镜的镜头能进行清洁，所以应用擦镜纸擦拭．

故选C．

填空题

Part 4


Questions 26-45


·Read the following text and decide which answer bestfits each space.
·For questions 26-45, mark one letter A, B, C or D on the Answer Sheet.

Newspapers


Who won the World Cup 1994 football game What happened at the United Nations How did the critics like the new play When an event takes place, newspapers are on the streets (26) the details. (27) anything happens in the world, reporters are on the spot to (28) the news.
Newspapers have one basic (29) to get the news as quickly as possible from its source, from those who make it to those who want to (30) it. Radio, telegraph, television, and (31) inventions brought competition for newspapers. So did the development of magazines and other means of communication. (32) this competition merely spurred the newspapers on. They quickly made (33) of the newer and faster means of communication to improve the speed and (34) the efficiency of their own operations. Today more newspapers are printed and read than ever before.
Competition also led-newspapers to branch out into many other fields. Besides keeping readers (35) of the latest news, today’s newspapers (36) readers about politics and other important and serious matters. Newspapers influence readers’ economic choices (37) advertising. Most newspapers depend on advertising for their very (38) Newspapers are sold at a price that (39) to cover even a small fraction of the cost of production. The main (40) of income for most newspapers is commercial advertising. The (41) in selling advertising depends on a newspaper’s value to advertisers. This is measured (42) circulation. How many people read the newspaper Circulation depends (43) on the work of the circulation department and on the services or entertainment (44) in a newspaper’s pages. But for the most part, circulation depends on a newspaper’s value to readers as a source of information (45) the community, city, country, state, nation, and world—and even outer space.

A．on

B．through

C．under

D．of
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单项选择题

当气体灭火系统设置自动启动方式时，应在接到（）个独立的火灾信号后才能启动。

A．1 

B．2 

C．3 

D．4
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