已知盐酸普鲁卡因的氯化钠等渗当量为0.18，若配制0.5%盐酸普鲁卡因等渗溶液200ml，需加入多少克氯化钠
A. 0.72g
B. .0.18g
C. 0.81g
D. 62g
E. 33g
查看答案
There are 1 billion people in the world who study English every year.[音频]
A. 对
B. 错
The European Union uses only English in its meetings.[音频]
A. 对
B. 错
More than 175 countries use English as the official language.[音频]
A. 对
B. 错
The speaker says that all Internet users know English.[音频]
A. 对
B. 错
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