Titration of Ca2+ and Mg2+ in a 50.00-mL sample of hard water required 23.65 mL of 0.01205

Question:

Titration of Ca2+ and Mg2+ in a 50.00-mL sample of hard water required 23.65 mL of 0.01205 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate Mg2+ as Mg(OH)2(s). The supernatant liquid was titrated with 14.53 mL of the EDTA solution. Calculate
(a) The total hardness of the water sample, expressed as ppm CaCO3.
(b) The concentration of CaCO3 in the sample in ppm.
(c) The concentration of MgCO3 in the sample in ppm.