采用屏护措施将带电体隔离开来,可以有效地防止()触电。
A、间接接触
B、直接接触
C、单相触电
参考答案:B
I have two sweaters,one is made of cotton,and______ is made of wool. [ ]
A. other
B. the other
C. others
D. another
5种药物的LD50和ED50值如下所示,最有临床意义的药物是
A.LD50:25mg/kg,ED50:15mg/kg
B.LD50:25mg/kg,ED50:5mg/kg
C.LD50:25mg/kg,ED50:10mg/kg
D.LD50:25mg/kg,ED50:20mg/kg
E.LD50:50mg/kg,ED50:25mg/kg