# $HNO_3$ used as a reagent has specific gravity of $1.42 mL^{-1}$ and contains $70\%$ by strength $HNO_3$. Calculate Volume of acid that contains 63g pure acid.
$(a)\;60 mL\qquad(b)\;63.38mL\qquad(c)\;65mL\qquad(d)\;70mL$