Who can tell me the ____ way to learn English?[ ]
A. good
B. better
C. best
D. well
答案:C
正八边形的每个内角为( )
A.120°
B.135°
C.140°
D.144°
变频器的许可人口温度为()。
A、敞开机架型-10~45℃
B、敞开机架型-10~450F
C、敞开机架型-20~30℃
D、敞开机架型0~45℃