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【单选题】
—How long have you been writing letters in English? — . [ ]A.
Since six years
B.
For 1998
C.
For six years
D.
Six years ago
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举一反三
【简答题】A ring network is fast because all the data travel in the same_________ .
【判断题】When one computer in the bus or ring network breaks down, the whole network may fail to work.
A.
正确
B.
错误
【简答题】为什么说霸权主义、强权政治依然是威胁世界和平与稳定的主要根源？
【单选题】Which of the following connectivity issues is likely to occur within a token ring network?（）
A.
Crosstalk
B.
Broadcast storm
C.
Duplex mismatch
D.
Collision