A.≥3000g B.≥3500g C.>3500g D.≥4000g E.>4000g
A.0.5mg/L B.1.0mg/L C.1.5mg/L D.2.0mg/L E.2.5mg/L
A.10μg B.50μg C.100μg D.500μg E.1000μg