浮动床的进水浊度应小于（）mg/L。
A.2
B.5
C.10
D.15
参考答案：A
I prefer________TV to going shopping with my mother. [ ]
A. to watch
B. watch
C. watching
D. watched
肺气肿时胸部叩诊音为（）
A.清音
B.鼓音
C.实音
D.浊音
E.过清音
