管式换热器应（）排污1次。
A、每周
B、每月
C、每小时
D、每天
参考答案：D
In the old days, the boss often _________ his men work more than 8 hours a day.[ ]
A. had
B. let
C. asked
D. made
上述处方中糊精的作用是
A．乙酰水杨酸30gB．淀粉10gC．酒石酸0.4gD．滑石粉适量E．10％淀粉浆适量制成片剂1000个剂量单位
