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问题 选择题

已知m，n是关于x的一元二次方程x2﹣3x+a=0的两个解，若（m﹣1）（n﹣1）=﹣6，则a的值为（　　）

A．﹣10

B．4

C．﹣4

D．10

答案

C.

题目分析：利用根与系数的关系表示出m+n与mn，已知等式左边利用多项式乘多项式法则变形，将m+n与mn的值代入即可求出a的值．

根据题意得：m+n=3，mn=a，

∵（m﹣1）（n﹣1）=mn﹣（m+n）+1=﹣6，

∴a﹣3+1=﹣6，

解得：a=﹣4．

故选C.

单项选择题

我国“十一五”规划纲要提出，在本规划实施的中期阶段，要对规划实施情况进行中期评估。对中期评估报告进行审议的机构是( )。

A．全国人民代表大会
B．国务院
C．全国人民代表大会常务委员会
D．国家发展和改革委员会
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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] make [B] publish [C] know [D] write
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