A.压缩空气 B.普通空气 C.高纯空气 D.优级空气
A.0.1MPa B.0.01MPa C.0.001MPa D.0.0001MPa
A.1.56g±0.02g B.1.52g±0.02g C.1.50g±0.02g D.1.62g±0.02g