1, You are a scientist in a lab researching how the concentration of platinum within catalytic converters will affect the efficiency of hydrocarbon breakdown into CO2 and O2. Platinum is an expensive metal. You are told that the catalytic converters you were given to test contain 3.0 μg/kg, 4.0 μg/kg,4.5μg/kg, 5 μg/kg, 5.5μg/kg, 6 μg/kg, and 6.5μg/kg of platinum. Each converter is exposed to the same volume of gas exhaust from the same vehicle and you measure the CO2, and O2, produced. The results are as followed:

Tooth enamel consists mainly of the mineral calcium hydroxyapatite, ca_10(po_4)_6(oh)_2. trace elements in teeth of archaeological specimens provide anthropologist with clues about diet and diseases of ancient people. students at hamline university measured strontium in enamel from extracted wisdom teeth by atomic absorption spectroscopy. solutions with a constant total volume of 10.0 ml contained 0.726 mg of dissolved tooth enamel plus variable concentrations of added sr. added sr find the concentration of sr in the 10 ml sample solution in parts per billion = ng/ml. find the concentration of sr in tooth enamel in parts per million = mu g/g.