A.20%~50%、75mm B.10%~50%、75mm C.20%~30%、75mm D.20%~50%、80mm
A.≤1% B.≤1.5% C.≤2% D.≤2.5%
A.≤2%、≤7% B.≤1%、≤8% C.≤2%、≤8% D.≤1%、≤7%