A.2/3處 B.1/2處 C.1/3處 D.1/4處
A.路基面?zhèn)葴?br /> B.路塹邊坡 C.天然護(hù)道 D.路塹隔帶
A.1:1 B.1:1.25 C.1:1.5 D.1:1.75