交换机根据MAC地址寻址，路由器根据（）地址寻址
A.MAC
B.IP
C.ID
D.LOID
参考答案：B
蒸汽压力越高，其对应的饱和温度也越高。（）
The student was about to ____ the question, when suddenly he found the answer. [ ]
A. arrive at
B. work out
C. give up
D. work on
