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问题 填空题

已知烟碱（尼古丁）的化学式为C10H13N2，其相对分子质量为          ；各元素的质量比为              。（2分）

答案

161；120∶13∶28

 

题目分析：根据相对分子质量为化学式中各原子的相对原子质量之和，故烟碱（尼古丁）的化学式为C10H13N2，其相对分子质量为：12×10+1×13+ 14×2=161；元素的质量为原子的相对原子质量乘以原子个数，故各元素的质量比为12×10：1×13：14×2=120∶13∶28。

多项选择题

下列关于中外合资经营企业财务与会计管理的说法中，正确的是（）

A．合营企业原则上采用人民币为记账本位币，但经合营各方商定也可采用某一种外国货币为记账本位币。以外国货币记账的合营企业，无须另编折算成人民币的会计报表。

B．合营企业设总会计师，必要时可以设副总会计师。

C．合营企业必须设审计师，负责审查、稽核合营企业的财务收支和会计账目，向董事会、总经理提出报告。

D．合营各方的出资证明书应当经中国注册会计师验证和出具证明，方为有效。
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填空题

Do you live in a big city? Do you like the traffic in your city?

There are too m___1___ accidents in big cities. Accidents often h__2__ when people are not careful, especially when they want to c__3__ the road. Why does it happen sometimes? Let me tell you.

When it rains, people are in a h__4__ because they don’t want to get w__5__. They often go across the road q__6__. Often they can’t see c__7__ because they hold umbrellas in front of them. Then accidents may happen at that time. Everyone knows that cars take l__8__ time to stop when it’s raining. So we must be more c__9__ if we want to be safe. Remember everyone has only one l__10__ and we must protect ourselves well.
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