断面面积均为A=0.48m2的正方形管道、宽高比为3的矩形管道和圆形管道,各自的水力半径分别为()。
A:R正=0.174、R矩=0.15、R圆=0.195
B:R正=0.15、R矩=0.174、R圆=0.195
C:R正=0.1、R矩=0.5、R圆=0.5
D:R正=0.195、R矩=0.15、R圆=0.174
出自:中央空调系统操作员