DH80空压机放空阀是（）
A.电动截止阀
B.气动薄膜调节阀
C.电动闸阀
参考答案：C
分析性职业流行病学调查，不包括
A．病例—对照研究B．回顾性调查C．队列研究D．前瞻性研究E．横断面调查
After theearthquake,the injured were cared _____ in the hospitals ortaken by air to the hospitals
in the other cities. [ ]
A. of
B. for
C.after
D. with
