A.0.1mg/m3B.0.01mg/m3C.0.001mg/m3D.0.0001mg/m3
A.±1℃B.±5℃C.±10℃D.±15℃
A.正對(duì)B.背對(duì)C.側(cè)對(duì)D.面對(duì)