单项选择题
A.0.5mB.1mC.不超过2mD.大于2m
A.50kPaB.60kPaC.70kPaD.73.5kPa
A.1B.1/2C.1/3D.1/4
A.不小于0.5mB.不小于1mC.不大于0.5mD.不大于1m
微信扫一扫,加关注免费搜题