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阅读下面短文,完成下面3个小题 科学家在地面实验室的实验表明,一些小分子物质经紫外线的照射可以生成氨基酸。光谱分析表明,星际空间存在着这样的小分子物质。科学家还利用卫星进行了有关实验,这样的小分子物质在太阳紫外线照射下生成了氨基酸大分子。因此,一些科学家认为彗星在空间运行时会吸附上这些大分子;而且,由于彗星结构松散,其吸附的大分子在紫外线的照射下更容易产生类生命物质。它们虽有类似原始生命的结构,但不能自我复制。 据此,有的科学家推测;地球生命之源可能来自40亿年前坠入地球海洋的一颗或数颗彗星。当时地球大气密度很高,减慢了彗星下坠的速度,使彗星表面的温度不会过高,从而保护了彗核表面的类生命的物质。当彗核坠入海洋后,它们得到了再发展的条件,便形成了更为复杂的系统(通常由上百个分子组成)。该系统只让氧气、水等小分子进出,而氨基酸等则不能进出,久而久之这种有序状态促成了该系统能自我复制,进而导致了生命的诞生。 “它们虽具有类似原始生命的结构”中的“它们”指的是()。

A. 经紫外线照射的小分子物质
B. 类生命物质
C. 接受紫外线照射过的氨基酸
D. 大分子物质

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Questions 28-30Decide which THREE of the following statements are true, according to the speakers, and write the appropriate letters on your answer sheet in any order.A. People with high blood pressure should consult doctors before starting fitness routines.B. An aerobic fitness assessment is done while a person is exercising.C. An aerobic fitness assessment measures lung capacity.D. Health club employees are better at assessing physical fitness than doctors.E. Doctors might recommend changing fitness routines according to test results.F. People shouldn’t exercise at all whilst injured. 28()

Do the following statements agree with the information given in the textWrite TRUE if the information in the text agrees with the statement.Write FALSE if the information in the text contradicts the statement.Write NOT GIVEN if there is no information on this. Being tall in itself makes a person healthier.()

易致子代女性发生阴道癌的药物是

A. 庆大霉素
B. 苯妥英钠
C. 阿托品
D. 己烯雌酚
E. 沙利度胺

Questions 23-26 According to the information given in the text, choose the correct answer from the choices given. The unemployment rate in Aberdeen is ()

A. slightly lower than the average for Britain.
B. much lower than the average for Britain.
C. less than 10% of the average for Britain.

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