单项选择题
A.5mm;3mm B.6mm;4mm C.3mm;4mm D.5mm;4mm
A.不准 B.可以 C.不宜 D.不应当
A.0.6m×0.6m B.0.4m×0.5m C.0.5m×0.5m D.0.5m×0.6m