A.準(zhǔn)大氣壓 B.負(fù)壓 C.絕對壓力 D.工程大氣壓
A.1m2 B.2m2 C.0.01m2 D.0.1m2
A.0~1.6Mpa,0.5級 B.0~2.5Mpa,0.35級 C.0~4Mpa,0.25級