单项选择题
A.100 B.110 C.125 D.137.5
A.矩形 B.圆形 C.梯形 D.拱形
A.不宜大于100mm,不应大于5% B.不宜大于100mm,不应大于3% C.不宜大于150mm,不应大于5% D.不宜大于150mm,不应大于3%