配置了上行速链路后，交换机的会增加（）
A、网桥优先级
B、端口优先级
C、路径成本
D、根路径成本
参考答案：B
Having lost all his _____ in the fire, the man had to depend on his friends and relatives for a living. [ ]
A. possessions
B. paragraphs
C. relations
D. conferences
河长制起源于（）省份
A.浙江
B.江西
C.江苏
D.上海
