脐风多在生后几日内发病：（） A.1～2天 B.3～4天 C.4～7天 D.7～10

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问题单项选择题 A1/A2型题

脐风多在生后几日内发病：（）

A.1～2天

B.3～4天

C.4～7天

D.7～10天

E.10～20天

答案

参考答案：C

选择题

下列各题计算正确的是（　　）

A．x⁶÷x³=x²

B．x⁶-x³=x³

C．（-x）⁴÷（-x）²=-x²

D．x²ⁿ÷xⁿ=xⁿ

填空题

根据句子意思，用括号中所给单词的适当形式填空。

1. Peter is much ______ (tall )than Kitty.

2. September is the ______ (nine) month of the year.

3. You should listen to your teacher ______ (careful) in class.

4. I would rather ______ (stay) at home than go shopping with you.

5. Sandy was ______ (happy) because she failed in the maths exam yesterday.