Sulfide (S), 1000µg/mL in Water, 3 x 20ml

Cu @ 1000 µg/mL in 5% HNO3, 100ml

Method 200.8/1638/1640 Internal Standard, 10µg/ml in 2%-HNO3, 4x25ml

Arsenic, 1000ug/ml, 100ml