Colton has an ice cube that has a mass of 4 grams. he places it in a sealed container and then puts it in the microwave on high. the ice cube melts after a few seconds. he removes the sealed container with the melted ice cube and checks the mass again. which sentence best describes what colton discovers? a) the mass of the melted ice cube was less than 4 grams. b) the mass of the melted ice cube was more than 4 grams. c) the mass of the melted ice cube could not be determined. d) the mass of the melted ice cube remained the same at 4 grams.

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.