单项选择题
A.30mmB.40mmC.50mmD.60mm
A.半砖(120mm),一砖(240mm) B.半砖(120mm),1/4砖(60mm) C.一砖(240mm),一砖半砖(360mm) D.一砖(240mm),1/4砖(60mm)
A.1.8m;2mB.1.8m;3mC.2m;1.8mD.3m;1.8m