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问题 单项选择题

设计数据库的存储结构属于( )。

A．需求分析

B．概念设计

C．逻辑设计

D．物理设计

答案

参考答案：D

解析： 物理设计阶段主要解决选择文件存储结构和确定文件存取方法的问题，包括：选择存储结构、确定存取方法、选择存取路径、确定数据的存放位置。

填空题

利用如图1所示电路，在研究通过导体的电流跟电阻的关系时，要保持导体两端电压不变。实验中，不断改变Rx的阻值，调节滑动变阻器使伏特表示数保持不变，得到了I与R 的关系图像，如图2所示由图像可以得出的结论是_________________________；此次实验中，伏特表的示数始终保持____________V不变．

                                                                     图1                                                                   图2 

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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) .

3（）

A.put

B.return

C.set

D.send
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