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问题 选择题
椭圆的一个焦点到相应准线的距离为
5
4
，离心率为
2
3
，则椭圆的短轴长为（　　）
A．
5
2
B．4
5
C．2
5
D．
5
答案

由题意可得

a2
c
-c=
5
4
，
2
3
=
c
a

联立方程可得：a=

3
2
，c=1，由b2=a2-c2=
9
4
-1=
5
4
⇒b=
5
2
．

故选A．

选择题

莎士比亚说：“老老实实最能打动人心。”这句话说的是：[ ]

A．老实人好欺负

B．只有诚实才能打动人心，获得人们的信任

C．老实人希望得到别人的信任

D．人不能过于老实
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单项选择题

A variety of illegal acts committed by people in the course of their employment, for their own personal gain, are collectively known as white-collar crime. Embezzlement, theft and trading securities (1) insider information are common forms of white-collar crime. The majority of cases involve low-level employees who steal because they are under (2) financial stress. Many plan to (3) the money back as soon as possible but may never do so. Their crimes are usually never (4) because the amounts of money are small, and no one notices the (5) .

(6) , there are some very large cases of white-collar crime, such as multimillion-dollar stock market or banking seams that take years to discover and are extremely difficult and expensive to (7) .

White-collar crime is not (8) to the business sector. Government employment, especially (9) the city level, also provides opportunities to (10) one’s pockets. (11) , building inspectors accept bribes and full-time employees receive (12) payments.

Although white-collar crime is less (13) than street crime, it involves (14) more money and harm to the public than crimes committed by street criminals. It is (15) that there are more criminals (16) the office suites than in the streets, yet the (17) of white-collar makes it difficult to uncover the offenses and pursue the offenders. As the economy (18) from manufacturing to services and electronic commerce, opportunities for white-collar crime (19) , while the technology needed to stop such crimes will (20) .

17（）

A.nature

B.feature

C.property

D.essence
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