C125M×3-2RH离心式压缩机的电机转速()。
A.3400r/min
B.3600r/min
C.3500r/min
D.2975r/m
参考答案:D
-What are you busy with ?
-The conference _______ in our city next week.
A.held
B.will be held
C.be holding
D.to be held
新生儿呼吸窘迫综合征生后几天内死亡者最多()
A.1天
B.2天
C.3天
D.5天
E.7天