试简述道岔分组的方法。
Which one of the following characteristics is true regarding the use of hubs and switches?（） [" Hubs can have their ports be configured with VLANs"," Using hubs is costly with regard to bandwidth availability."," Switches can not forward broadcasts."," Switches are more efficient than hubs in processing frames."," Switches increase the number of collision domains in the network."]
躁狂症与躁郁症。
起重机上的滑轮中的滚动轴承一般使用（）润滑脂。 ["齿轮油","机械油","润滑脂"]
工程保险当中，以下不是按保险标的划分的是（）。 ["A.建筑工程一切险 ","B.工程项目其他险 ","C.人员伤亡保险 ","D.财产损失保险"]
C语言适用范围大
