TCAS天线的特点是（）A、天线有方向性,且4个导线接头不能接错，

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问题单项选择题

TCAS天线的特点是（）

A、天线有方向性,且4个导线接头不能接错，天线馈线长度误差不能大于5英寸

B、4个导线有方向性

C、天线为无方向性天线,但馈线有方向性

答案

参考答案：A

填空题

用所给词的适当形式填空。

1. My school will ____________ (has) a concert next week.

2. — Can Tom play the piano? — No, he ____________ (can).

3. Next Friday is Children's Day, ____________ (is) it?

4. My mother is ____________ (buy) a cake for the birthday party.

5. Mocky ____________ (play) the drums very well.

6. We won't ____________ (visiting) Uncle Booky tomorrow.

7. What will he ____________ (does) this weekend?

8. What will you do if it ____________ (rain) tomorrow?

9. Are you ____________ (kid)?

10. Mike really can ____________ (plays) football well.

填空题

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