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问题 选择题

下列化学方程式正确的是（　　）

A．Cu+2HCl=CuCl2+H2↑

B．BaCl2+2KOH=Ba（OH）2↓+2KCl2

C．Fe+2KNO3=2K+Fe（NO3）2

D．NaOH+HNO3=NaNO3+H2O

答案

A、铜排在金属活动顺序表中氢的后面，不能与酸反应，故A错误；

B、首先氢氧化钡溶于水，这个反应不能发生，再者氯化钾的化学式书写错误，故B错误；

C、此反应不能发生，铁排在钾的后面，不能置换出钾，故C错误；

D、反应原理和化学方程式都正确，故D正确；

故选D

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)

12（）

A.personnel

B.locality

C.natives

D.individuals
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判断题

根据《长途光缆波分复用（WDM）传输系统工程设计规范》（YD/T5092—2005），WDM设备的安装必须进行抗震加固，其加固方式应符合YD5059-2005《电信设备安装抗震设计规范》的相关技术要求。
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