A.當(dāng)2m小于hb小于等于5m,墜落半徑為3mB.當(dāng)5m小于hb小于等于15m,墜落半徑為3mC.當(dāng)15m小于hb小于等于30m,墜落半徑為4mD.當(dāng)hb大于30m時,墜落半徑為5m
A.0.5~1.0米B.小于0.5米C.1米~2米D.不小于1.0米
A.1步B.2步C.3步D.4步