A.0.10mg/L B.0.20mg/L C.0.30mg/L D.0.50mg/L
A.鐵 B.鎳 C.鈷 D.鉍
A.磺基水楊酸鈉 B.二乙基二硫代氨基甲酸鈉 C.乙二胺四乙酸二鈉 D.乙酸—乙酸鈉