A.探測器至墻壁、梁邊的水平距離為0.5m B.探測器至墻壁、梁邊的水平距離為0.3m C.探測器至墻壁、梁邊的水平距離為0.7m D.探測器至墻壁、梁邊的水平距離為1.0m
A.0.5,0.4 B.0.5,0.5 C.0.4,0.5 D.0.4,0.4
A.0.5m B.0.4m C.0.3m D.0.2m