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问题 单项选择题

数据库(DB)、数据库系统(DBS)和数据库管理系统(DBMS)之间的关系是（ ）。

A．DB包括DBS和DBMS

B．DBS包括DB和DBMS

C．DBMS包括DB和DBS

D．3者属于平级关系

答案

参考答案：B

解析：数据库(DB)是指存储在计算机存储设备上、结构化的相关数据的集合，数据库系统(DBS)是指引进数据库技术后的计算机系统，数 据库管理系统(DBMS)是为数据库建立、使用和维护而配置的软件系统。它们之间的关系是数据库系统包括数据库和数据库管理系统。

填空题

Perhaps, every county suffered from inflation once or more times. Inflation is an economic condition in (B1) prices for consumer goods (B2) , and the (B3) of money or purchasing power decreases. There are three causes of inflation. The first and most important cause may be excessive government spending. For example, in order to (B4) a war or carry (B5) social programs, the government may spend more money than it has received through taxes and other revenues, thus creating a deficit. In order to (B6) this deficit, the Treasury Department can simply (B7) the money supply by issuing more paper money to (B8) the debts of government. This increase in the money supply will cause the value of the dollar to (B9) decrease. The second cause of inflation occurs when the money supply increases faster than the supply of goods. (B10) people have more money, they will run out to buy popular goods (B11) televisions and computers, for example, and a shortage will result. Industry will then produce more, at higher prices, to (B12) demand. (B13) , if people think that the prices of popular goods are going up, they will buy and even borrow money at high (B14) rates to pay for them. Finally, if labor unions demand that workers’ wages (B15) or (B16) the high cost of living, industry will meet this demand and add other costs of production on the (B17) . (B18) summary, all of these causes can (B19) inflationary problems that can affect the welfare of a nation. However, of these three causes, (B20) government spending may be the most important.

A．value

B．price

C．cost

D．spending
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选择题

电场中某区域的电场线分布如图所示．a、b是电场中的两点，分别用Ea、Eb表示a、b两点电场强度的大小，用φa、φb表示a、b两点的电势．下列判断正确的是（　　）

A．Ea＜Eb，φa＜φb

B．Ea＜Eb，φa＞φb

C．Ea＞Eb，φa＜φb

D．Ea＞Eb，φa＞φb
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