A.大于 B.等于 C.小于 D.小于或等于
A.0.28MP(40psi) B.0.35MPa(50psi) C.0.4MPa(60psi) D.0.685MPa(100psi)
A.3mg/m3(2ppm) B.30mg/m3(20ppm) C.5.4mg/m3(2ppm) D.2mg/m3(5.4ppm)