A.1-5% B.4.3~19.0% C.12.5-74.2%
A.1~10% B.0.1~5% C.1.1~12.5% D.1.1~15%
A.精密儀器 B.電氣一設(shè)備 C.金屬氧化物 D.圖書檔案