刮板运输机出现下列（）时要停机进行处理后才能开车，严禁强行开车。
A. 刮板链出槽
B. 链板机上有矸石
C. 飘链
D. 链板机上有水
查看答案
Why is QoS important in a converged network?（）
A. Because data does not need to arrive intact, so data transfer rates can be variable
Because lost voice-data packets must be retransmitted
C. Because voice data packets should arrive quickly and sequentially, and with no lost data
D. Because voice data packets must follow a single dedicated path through the network
磁石电话的音频线路阻抗是600Ω。
A. 正确
B. 错误
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