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问题 填空题
若l的方向向量为（2，1，m），平面α的法向量为（1，
1
2
，2），且l⊥α，则m=______．
答案

∵l⊥α，

∴l的方向向量为（2，1，m）与平面α的法向量为（1，

1
2
，2）平行，

∴(2，1，m)=λ(1，

1
2
，2)．

∴

2=λ
1=
1
2
λ
m=2λ
，解得m=4．

故答案为4．

阅读理解

根据短文回答问题。

Amy: What does your father do?

Jenny: He is a teacher.

Amy: Where does he work?

Jenny: He works in a school.

Amy: How does he go to work?

Jenny: He goes to work by bus.

Amy: What does your mother do?

Jenny: She is a salesperson.

Amy: Where does she work?

Jenny: She works in a shop.

1. What does Jenny's father do?

________________________________________________________

2. Where does he work?

________________________________________________________

3. What does Jenny's mother do?

________________________________________________________
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单项选择题

当用户按下并释放键盘上的某个键时，（）事件发生。

A.DblClick

B.SetFocus

C.KeyPress

D.GotFocus
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