口服氟片每次处方氟化钠总剂量不得超过
A.80mg
B.90mg
C.100mg
D.120mg
E.140mg
参考答案:D
I'm very tired. I can _____ run. [ ]
A. always
B. hardly
C. usually
D. sometimes
遮拦与带点部分的距离,10kv及以下不得小于()mm。
A.0.2
B.0.25
C.0.3
D.0.35