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问题 选择题

2N表示（   ）

A．2个氮原子

B．2个氮分子

C．4个氮原子

D．4个氮分子

答案

答案：A

根据化学符号“2N”表示的含义判断，N是氮的元素符号，从宏观上可表示氮元素，从微观上表示一个氮原子，但是在元素符号前加上数字就只有微观含义，只能表示2个氮原子．

故选A

单项选择题

四、根据以下资料， 回答131--135题 2010年，我国进出口贸易总额为29727.6亿美元，同比增长34.7% 2010年，我国机电产品出口9334.3亿美元，同比增加30.9%; 高新技术产品出口4924.1亿美元，同比增长30.7%。 船舶、汽车零部件出口保持较快增长，其中船舶出口同比增长的44.5%，汽车零部件出口同比增长44.1% . 2010年，机电产品进口额达到6603.1亿美元，同比增长34.4%，高新技术产品进出口额达到4126.1亿美元，同比增长33.2% 2010年我国进出口贸易情况

2009年我国进出口贸易总额约多少万亿美元（）

A．1.6

B．2.2

C．2.6

D． 3.0
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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)

9（）

A.option

B.span

C.prototype

D.range
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