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问题 填空题

人造羊毛的主要成分为，此物质可由以下三种途径合成，已知A是石油分馏的一种产品。

回答下列问题：

1写出A的分子式________________，D的结构简式__________________

2在反应①～⑥中，属于加成反应的是　　　　

3写出反应⑥的化学方程式：_____________________________________

4从能源和环保的角度看，你认为最有发展前景的是　　　　，其中理由是____________________________________________________

答案

1C4H10　

由于生成可推知C应为

单项选择题

我国某旅行社2003年11月组织5次旅游，其中3次在境内各地旅游，收取旅游费 565000元，其中替旅客支付的餐饮、门票、交通、住宿费用200000元，支付给本单位司机工资及补助6000元，导游费8000元；组织到境外旅游2次，收取旅游费520000元，其中一次改为境外旅游企业接团，支付给境外旅游企业接团费150000元。该企业上述业务应纳营业税为( )元。

A．46750

B．36050

C．36750

D．54250
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单项选择题

Few scientific fields are as full of risk as that of research into human intelligence. The two questions that (1) over and over again are "is it a result of nature or nurture" and "does race make a difference"

Making (2) comments about the second question can be a (3) move, as James Watson, a co-discoverer of DNA structure, recently found. He suggested that he was " (4) about the prospect of Africa" (5) "all our social policies are based on the fact that their intelligence is the same as ours (white people) (6) all the testing says not really". Such (7) by Dr. Watson are not merely (8) , they are scientifically weird. If the term (9) has any useful scientific meaning, then Africa, the continent where modern humanity began, is most racially diverse. The resulting (10) among the public forced Dr. Watson to leave his laboratory.

(11) , the study of the first question (12) between intelligence and genetics— has some wiser practitioners. One of them, Terrie Moffitt, of King’s College, has just (13) a project judging the relative importance of nature and nurture. Dr. Moffitt’s team (14) the effect on intelligence of breastfeeding, but in a genetic context. Previous studies have shown that breastfed children are more intelligent, (15) about six IQ points, than those given baby formulas.

The team, however, (16) the involvement of a gene called FADS2, which comes in two varieties, known as C and G. The researchers (17) if these two varieties interacted differently with breast milk. (18) on data from two groups of people, they found that the intelligence increase associated with breastfeeding only happened to people having (19) at least one copy of the C variety. The effect did not. (20) on the social classes or IQs of the parents.

14（）

A.had

B.examined

C.discovered

D.suggested
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