生川乌药材中含有的剧毒成分是（）
A.异喹啉类生物碱
B.双酯类生物碱
C.乌头多糖
D.双蒽酮苷类
E.乌头胺
参考答案：B
逻辑题。
1. A man sells water. What does he first think of when he sees a river?
Answer: _____
2. A car travels at a speed of 40 mph over a certain distance and then returns over the same distance
at a speed of 60 mph.What is the average speed for the total journey?
母线停电操作时，电压互感器应最后停电，送电时先合电压互感器。
