A.3 B.4 C.5 D.6
A.跨越點(diǎn) B.交叉點(diǎn) C.測(cè)站點(diǎn) D.中心點(diǎn)
A.2%~4% B.3%~5% C.4%~5.5% D.5%~5.5%