单项选择题
A.800pa;800pa B.600pa;1200pa C.1000pa;800pa D.800pa;1000pa
A.屋面汇水面积 B.屋面情况 C.重现期降雨强度 D.雨水水流速度
A.1;0.75m/s B.0.75;1m/s C.1;1m/s D.0.75;0.75m/s