A.0.5 B.0.6 C.0.7 D.0.8
A.300mm B.400mm C.500mm D.750mm
A.內(nèi)表面,下面0.2m,為0.2m的倍數(shù) B.外表面,下面0.2m,為0.2m的倍數(shù) C.內(nèi)表面,下面0.1m,為0.1m的倍數(shù) D.外表面,下面0.1m,為0.1m的倍數(shù)