方形管道的边长和通过的流量同时减小一半，则雷诺数( )。
A．等于原值的四倍
B．等于原值的两倍
C．保持不变
D．等于原值的一半
参考答案：C
,the idea of having to work under a woman defeated him.
A．Wanting the job very much
B．Although wanting the job badly
C．Though he wanted the job very much
D．He wanted the job badly
安静状态下，人体散热最主要的方式是（）
A.辐射
B.对流
C.传导
D.蒸发
E.上述均不是
