A.機(jī)械性噪聲 B.電磁性噪聲 C.空氣動(dòng)力噪聲
A.0.1≤p<1.6 B.1.6≤p<10 C.10≤p<100
A.小于0.5% B.小于1.5% C.小于2.5% D.小于2.0%