A.100mm B.120mm C.140mm D.160mm且不小于層高的1/20
A.300mm B.250mm C.350mm D.400mm
A.Ⅰ、Ⅲ、Ⅳ B.Ⅰ、Ⅱ、Ⅳ C.Ⅰ、Ⅱ、Ⅲ D.Ⅰ、Ⅱ、Ⅲ、Ⅳ