眩晕的病理是
A．痰、气、火、风 B．气、血、痰、食 C．风、痰、火、虚 D．气、火、痰、瘀 E．气、火、痰、食
参考答案：C
制造方便，便于维修，自重也较轻，属于使用广泛的平托盘的是（）。
A.钢制平托盘
B.塑料制平托盘
C.高密度合成板托盘
D.木制平托盘
_____ hours do you exercise every day? [ ]
A. How many
B. How much
C. How often
D. How
