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问题 解答题

（2011•南京）从3名男生和2名女生中随机抽取2014年南京青奧会志愿者．求下列事件的概率：

（1）抽取1名，恰好是女生；

（2）抽取2名，恰好是1名男生和1名女生．

答案

解：（1）5名学生中有2名女生，，所以抽取1名，恰好是女生的概率为；

（2）共有20种情况，恰好是1名男生和1名女生的情况数有12种，所以概率为．

选择题

需加入适当的氧化剂才能实现的反应是（    ）

A PCl5PCl3            B. MnO2Mn2+

C.SO2SO32-            D. FeFe3O4
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单项选择题

Who won the World Cup 1994 football game What happened at the United Nations How did the critics like the new play (1) an event takes place, newspapers are on the streets (2) the details. Wherever anything happens in the world, reporters are on the spot to (3) the news.
Newspapers have one basic (4) , to get the news as quickly as possible from its source, from those who make it to those who want to (5) it.
Radio, telegraph, television, and (6) inventions brought competition for newspaper. So did the development of magazines and other means of communication. (7) , this competition merely spurred the newspapers on. They quickly made use of the newer and faster means of communication to improve the (8) and thus the efficiency of their own operations. Today more newspapers are (9) and read than ever before. Competition also led newspapers to branch out into many other fields. Besides keeping readers (10) of the latest news, today’s newspapers (11) and influence readers about politics and other important and serious matters. Newspapers influence readers’ economic choices (12) advertising. Most newspapers depend on advertising for very (13) .
Newspapers are sold at a price that (14) even a small fraction of the cost of production. The main (15) of income for most newspapers is commercial advertising. The (16) in selling advertising depends on a newspaper’s value to advertisers. This (17) in terms of circulation. How many people read the newspaper
Circulation depends (18) on the work of the circulation department and on the services or entertainment (19) in a newspaper’s pages. But for the most part, circulation depends on a newspaper’s value to readers as a source of information (20) the community, city, county, state, nation, and world—and even outer space.

[A] by [B] with [C] at [D] about
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