Given Density of a sample 0.9977 g/mL and the molar mass of Calcium Carbonate

Given Density of a sample 0.9977 g/mL and the molar mass of Calcium Carbonate (CaCO3) is 100.0 g/mol calculate the mass of calcium carbonate present in 50.0 mL sample of an aqueous Calcium Carbonate standard… assuming that the standard of hardness is 75.0 ppm (hardness due to CaCO3.