A.紙質(zhì)或紙板 B.木質(zhì) C.油質(zhì) D.碳質(zhì)
A.0.50% B.1% C.2% D.3%
A.0.5,1,0.5 B.1,0.5,1 C.5,1,0.5 D.3,0.5,1