虽然我们的手机可以发送信号，也可以接收信号，但是没有天线的。
查看答案
遵循802.11协议规范无线局域网使用CSMA/CD协议解决信道争用问题。( )
A. 对
B. 错
8[音频]
A. It boasts a fairly long history.
B. It produces construction materials.
C. It has 75 offices around the world.
D. It has over 50 business partners.
9
A. It has about 50 employees.
B. It was started by his father.
C. It is a family business.
D. It is over 100 years old.
10
A. Shortage of raw material supply.
B. Legal disputes in many countries.
C. Outdated product design.
D. Loss of competitive edge.
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