举例,挖土深度1m,放坡宽度0.75m,则放坡坡度为1:0.75
计算挖沟槽、基坑、土方工程量需要放坡,河北省定额规定人工挖一、二类土壤的放坡系数是( )A.1:0.250B.1:0.500C.1:0.330D.1:0.100