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问题 选择题

有A、B、C、D四种元素，已知A是地壳中含量最多的元素，B元素的原子失去一个电子后只剩下一个质子，C元素是人体中含量最高的金属元素，D-的电子层结构与氩原子相同。请回答：

A元素是       ；   由B元素组成的单质是        ；

D- 的粒子符号      ；    A、B、C三种元素组成化合物的化学式          。

答案

氧（或O）；氢气（或H2）；Cl-；Ca(OH)2。

题目分析：地壳中元素含量排在前四位的是：O、Si、Al、Fe ；B元素的原子失去一个电子后只剩下一个质子，说明该元素的质子数为1，是氢元素；C元素是人体中含量最高的金属元素，即为钙元素；D-是带一个单位负电荷的阴离子，即得到了一个电子后的电子层结构与氩原子相同，则是氯元素；O、H、Ca 三种元素组成化合物的化学式为Ca(OH)2。

单项选择题

()是由国务院组织制定并批准公布的，是为实施安全生产法律或规范安全生产监督管理制度而制定并颁布的一系列具体规定，是我们实施安全生产监督管理和监察工作的重要依据。

A．《宪法》

B．安全生产行政法规

C．安全生产规章制度

D．地方性安全生产法规
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单项选择题

At some time in your life you may have a p desire to do something strange or terrible. However, chances are that you don’t act on your impulse, but let it pass instead. You know that to commit the action is wrong in some way and that other people will not accept your behavior.
Perhaps the most interesting thing about the phenomenon of the behavior is how it can change over the years within the same society, how certain behavior and attitudes once considered taboo can become perfectly acceptable and natural at another point in time. Topics such as death, for example, were once considered so upsetting and unpleasant that it was a taboo to even tall about them. Now with the publication of important books such as "On Death and Dying" and "Learning to Say Goodbye", people have become more aware of the importance of expressing feelings about death and, as a result, are more willing to talk about this taboo subject.
One of the newest taboos in American society is the topic of fat. Unlike many other taboos, fat is a topic that Americans tall about constantly. It’s not taboo to tall about fat; it’s taboo to be fat. The "thin" look is thin, not fat.
In the work world, most companies prefer youthful-looking, trim executives to sell their image as well as their products to the public. The thin look is associated with youth, vigor and success. The fat person, on the other hand, is thought of as lazy and lacking in energy, self- respect. After all, people think, how can people who care about themselves, and therefore the way they look, permit themselves to become fat In an image-conscious society like the U.S., thin is "in", fat is "out".

In the U.S., the expression that thin is "in" and fat is "out" probably means ______.

A. thin is "diligent" and fat is "lazy"
B. thin is "fashionable" and fat is "unfashionable"
C. thin is "inside" and fat is "outside"
D. thin is "spiritless" and fat is "vigorous\
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