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问题 选择题

我国自主研制的复制型艾滋病疫苗，是把艾滋病病毒的核酸的几个重要片段逆转录后插入天花病毒DNA中，形成重组病毒疫苗。该疫苗具有复制能力，可以持续刺激免疫系统，使人产生较强的免疫能力。该疫苗研制过程中 [ ]

A．运用了RNA病毒容易突变的能力

B．运用了基因工程手段，使用质粒作为运载体

C．通常需要利用动物的细胞培养技术

D．该重组病毒的形成说明艾滋病病毒和天花病毒具有相同的遗传物质

答案

答案：C

解答题
已知函数f(x)=
1
3
x3-x2+1
（1）证明方程f（x）=0在区间（0，2）内有实数解；
（2）使用二分法，取区间的中点三次，指出方程f（x）=0（x∈[0，2]）的实数解x0在哪个较小的区间内．
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句型转换

根据第一句完成第二句，使两句意思相同或相近，每个空格限填一词。

1. Yao Ming received thousands of letters from his fans after his leg was broken.

    Yao Ming _______ _______ thousands of his fans after his leg was hurt.

2. Kate won't send e-mails to her e-friends this evening. I won't, either. 

    _______ Kate _______ I will send e-mails to our e-friends this evening.

3. Mr. Wang will be our maths teacher next term.

    Mr. Wang will _______ _______ maths next term.

4. Mrs Green gave birth to Lucy and Lily in 1992. They're twin sisters.

    Lucy is the _______ age _______ Lily.

5. Millie is interested in climbing mountains, and her sister is more interested in it.

    Millie is _______ interested in climbing mountains _______ her sister.

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