A 50.00 mL aliquot of a hard water sample is titrated with 15.00 mL of 0.0100 M EDTA, using Arsenazo indicator. A second 50.00 mL aliquot is made strongly alkaline with sodium hydroxide. A precipitate results. Calcein indicator is added to the solution. The sample then requires 10.00 mL of 0.0120 M EDTA for titration. Calculate for this sample (a) the molarity of the calcium present, (b), the molarity of the magnesium present, and (c) the total hardness of the water (as ppm of CaCO3 and MgCO3).