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27. The watch      unnoticed for several days       I found it.

    A. had laid; before       B. lay; after        C. had lain; before       D. laid; until

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26. If Sanlu Group      melamine to the milk, the babies      too much from kidney stone.

    A. didn’t add; would not suffer      

B. hadn’t added; wouldn’t have suffered

C. hasn’t added; wouldn’t have suffered

D. hadn’t added; would have suffered

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25. - How do you deal with the disagreement between the company and customers?

- The key     the problem is to meet the demand     by the customers.

    A. to solving; making            B. to solving; made

C. to solve; making                  D. to solve; made

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24. - Look! It       again.

- Yes. This in the third rain we       this month.

    A. will rain; shall we          B. is raining; have had

C. rains; had                 D. is going to rain; have had

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23. The H1N1 flu is spreading across the world at a frightening rate, with thousands of people     every day.

    A. to be infected      B. be infected     C. been infected      D. being infected

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22. The Roma originally lived in      India in      is now Pakistan.

    A. northern; when                   B. north; which       

C. northern; what                D. north; in which

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34.(7分)某小组在完成探究“温度是否会影响酶的活性”这个实验后提出一个问题:“酶活性受温度影响示意图”是否真的如教材所示,呈规则的、左右对称的抛物线呢?希望通过定量实验进行探究。以下是小组内同学们的讨论:

甲同学提出:可通过测单位时间内反应物的消耗量来测定酶的反应速率;

乙同学提出:先用酒精灯加热来制造高温条件,用排水法记录反应速率,实验装置如图1;

丙同学指出乙同学提出的实验方案有不合理的地方,温度过高酶会失活。他经过重新思考,定出了新的实验方案:先让酶由低到高预热成系列温度梯度,并与之相对应地加入过氧化氢,用排水法记录反应速率,实验装置如图2。

请回答:

(1)你认为甲同学的方案是否可行?      ,因为                

(2)小组采用了丙同学的实验方案,用系列温度梯度进行实验,得出不同温度下的反应速率,结果见下表:

请你根据上表数据,在坐标图中绘出酶活性受温度影响的曲线图。

(3)若用新鲜土豆研磨液代替上述新鲜猪肝研磨液,能否会出现

上述表格中类似的数据?            

(4)以上实验说明酶的催化作用需要           

(5)本实验得出的结论是                            

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