关于对称三相交流电源,以下论述正确的是()。A、对称三相交流电是由三组电压幅值相等的

题型:单项选择题

问题:

关于对称三相交流电源,以下论述正确的是()。

A、对称三相交流电是由三组电压幅值相等的电池组电源组成的

B、对称三相交流电源是由三个频率相同、最大值相等、相位互差120度的电动势组成

C、对称三个单相交流电源组成一个三相交流电源

D、对称三相交流电源是由三个频率相同、最大值相等,相位相同的电动势组成

考点:气体分馏装置操作工高级气体分馏装置操作工高级气体分馏装置操作工题库
题型:单项选择题

下列实验相关现象的描述正确的是(  )

A.磷在氧气中燃烧产生大量白色烟雾

B.蜡烛在氧气中燃烧生成二氧化碳和水

C.铁丝在氧气中燃烧,火星四射,生成黑色固体

D.硫在空气中燃烧,发出明亮的蓝紫色火焰

题型:单项选择题

比尔盖茨与()美国企业家合作创立了微软公司。

题型:单项选择题

关于伏立康唑的药动学特点,叙述正确的是()

A.主要在肾代谢

B.蛋白结合率高达90%

C.生物利用度高达90%

D.食物不影响其吸收

E.儿童和成人的药动学特点相同

题型:单项选择题

工人在外脚架上操作时,材料、工具等物不可斜靠在墙上,应该直接放置在脚手架上。( )

题型:单项选择题

Anthropology is the study of human beings as creatures of society. It (1) its attention upon those. physical characteristics and industrial techniques, those conventions and values, which (2) one community from all others that belong to a different tradition.

The distinguishing mark of anthropology among the social sciences is that it includes for serious study other societies (3) our own. For its purposes any social (4) of mating and reproduction is as significant as our own. To the anthropologist our customs and those of a New Guinea tribe are two possible social schemes for (5) a common problem, and in so far as he remains an anthropologist he is (6) to avoid any weighting of one (7) the other. He is interested in human behavior, not as it is shaped by one tradition, our own, but as it has been shaped by any tradition (8) He is interested in a wide (9) of custom that is found in various cultures, and his object is to understand the way in which these cultures change and (10) , the different forms through which they express themselves and the (11) in which the customs of any peoples function in the lives of the (12) .

Now custom has not been commonly regarded as a (13) of any great moment. The inner workings of our own brains we feel to be uniquely (14) of investigation, but custom, we have a way of thinking, is behavior at its most commonplace. (15) , it is the other way round. Traditional custom is a mass of detailed behavior more astonishing than (16) any one person can ever evolve in individual actions. Yet that is a rather (17) aspect of the matter. The fact (18) first rate importance is the predominant role that custom (19) in experience and belief, and the very great varieties it may (20)

14()

A.worth

B.worthwhile

C.worthy

D.rewarding

更多题库