足月妊娠时,正常胎心音频率为每分钟()
A.60~100次
B.80~120次
C.100~140次
D.110~160次
E.140~180次
参考答案:D
单项选择。
A bike is ____ than a bus and it's ____ than a car. [ ]
A. slower; faster
B. faster; slower
C. slower; slower
D. faster; faster
补贴