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问题 单项选择题

根据关系数据库规范化理论，关系数据库中的关系要满足第一范式，下面“学校”关系中，因哪一个属性而使它不满足第一范式

A．学校领导

B．学校人员

C．学校名称

D．学校编号

答案

参考答案：B

解析：解析：关系数据库中第一范式是：关系中的每个属性都是不可分割的。而本关系中，学校人员显然包括学校领导，所以它是可分割的。这样就不满足第一范式的条件。

单项选择题

降TC药物的胆酸螯合剂共同调脂机制是

A．阻止胆固醇从消化系统吸收促进胆固醇的降解
B．阻止胆酸从消化系统吸收，促进胆固醇随粪便排泄
C．阻止胆酸或胆固醇从肠道吸收，促进胆酸或胆固醇随粪便排泄，促进胆固醇降解
D．阻止胆酸或胆固醇从肠道吸收，而使胆固醇降解
E．促进胆酸从肠道吸收，从而促进胆固醇的合成
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单项选择题

Throughout the 19th century and into the 20th, citizens of the United States maintained a bias against big cities. Most lived on farms and in small towns and believed cities to be centres of (1) , crime, poverty and moral (2) Their distrust was caused, (3) , by a national ideology that (4) farming the greatest occupation and rural living (5) to urban living. This attitude (6) even as the number of urban dwellers increased and cities became an essential (7) of the national landscape. Gradually, economic reality overcame ideology. Thousands (8) the precarious (不稳定的) life on the farm for more secure and better paying jobs in the city. But when these people (9) from the countryside, they carried their fears and suspicions with them. These new urbanities, already convinced that cities were (10) with great problems, eagerly (11) the progressive reforms that promised to bring order out of the (12) of the city.

One of many reforms came (13) the area of public utilities. Water and sewerage systems were usually operated by (14) governments, but the gas and electric networks were privately owned. Reformers feared that the privately owned utility companies would (15) exorbitant (过渡的) rates for these essential services and (16) them only to people who could afford them. Some city and state governments responded by (17) the utility companies, but a number of cities began to supply these services themselves. (18) of these reforms argued that public ownership and regulation would (19) widespread access to these utilities and guarantee a (20) price.

17（）

A.degenerating

B.generating

C.regenerating

D.regulating
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