Winds generally move from areas of to areas of
a) high to low pressure
b) low to high altitude
c) the north to the south
d) cold to hot temperatures
6)
mars rotates by 360 degrees on its axis in 24 hours and 39 minutes. which of these is equivalent to 24 hours and 39 minutes on mars?
a) a day
b) a week
c) a year
d) a month

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.