A.30m B.55m C.80m D.120m
A.kg B.h C.m D.dB
A.結(jié)合層、面層、承重層、頂棚 B.結(jié)合層、承重層、頂棚、面層 C.面層、結(jié)合層、承重層、頂棚 D.基層、結(jié)合層、承重層、頂棚