SS7E型电力机车,两位置转换开关采用()驱动。
A、电磁传动装置
B、电空传动装置
C、电液传动装置
D、电动机驱动装置
参考答案:B
— I can't find my purse anywhere.
— You _____ have lost it while shopping. [ ]
A. may
B. can
C. should
D. would
中药浸膏片常用作润湿剂的物料是()
A.水
B.30%~70%乙醇
C.1%~2%CMCNa
D.3%~5%PVP
E.2%~5%HPMC