100 mL of a water sample contains 0.81 g of calcium bicarbonate and 0.73 g of magnesium bicarbonate. The hardness of this water sample expressed in…

$\displaystyle 100$ mL of a water sample contains $\displaystyle 0.81$ g of calcium bicarbonate and $\displaystyle 0.73$ g of magnesium bicarbonate. The hardness of this water sample expressed in terms of equivalents of $\displaystyle \mathrm{CaCO}_3$ is : (molar mass of calcium bicarbonate is $\displaystyle 162 \mathrm{~g} \mathrm{~mol}^{-1}$ and magnesium bicarbonate is $\displaystyle 146 \mathrm{~g} \mathrm{~mol}^{-1}$ )