一般正常孕妇的胎动数12小时内低于多少可考虑胎儿宫内缺氧（）。
A.≤5次
B.≤10次
C.≤12次
D.≤15次
E.≤20次
参考答案：B
It was the training he had as a young man made him such a good engineer.
A．what; that
B．which; that
C．that; which
D．that; what
当甩100%负荷时，超过额定转速3%以上的波峰不应超过4次。
