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问题 单项选择题

作两次数比较，已知n1、n2均小于30，总体方差不齐且分布呈极度偏态，宜用（）。

A．t检验

B．u检验

C．秩和检验

D．F检验

E．χ2检验

答案

参考答案：C

选择题

选择与句中画线部分意思相同或相近的词或短语。

1. Mary called him three times yesterday, but nobody answered.[ ]

A. visited

B. gave a message to

C. told

D. phoned 

2. Jim comes to Visit us sometimes. 

   That is always the happiest time for the whole family. [ ]

A. on time

B. all the time

C. at times

D. many times

3. Jimmy tried hard, and in the end he did it well. [ ]

A. at first

B. at the beginning

C. at the end

D. at last

4. —Oh, sorry, John. I forgot to post your letter.

    —That's all right. I'II post it myself.

[ ]

A. Never think about it

B. It doesn't matter

C. Don't be sorry

D. I don't care

5. —Hello! May I speak to the headmaster?

    —Hold on, please. [ ]

A. Speak louder

B. Wait a moment

C. Call again

D. Speak out
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单项选择题

根据神经系统WHO分类，恶性度最高的肿瘤是（）

A.毛细胞星形细胞瘤

B.间变型星形细胞瘤

C.胶质母细胞瘤

D.弥漫性星形细胞瘤

E.室管膜下巨细胞星形细胞瘤
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