$1.2 \mathrm{mL}$ of acetic acid is dissolved in water to make $2.0 \mathrm{L}$ of solution. The depression in freezing point observed for this strength of acid is $0.0198 °\mathrm{C}$. The percentage of dissociation of the acid is (Nearest integer) [Given : Density of acetic acid is $1.02 \mathrm{g}{ \mathrm{mL}}^{-1}$ Molar mass of acetic acid is $60 \mathrm{g}{\mathrm{mol}}^{-1}$
${\mathrm{K}}_{\mathrm{f}}\left({\mathrm{H}}_2\mathrm{O}\right)=1.85 \mathrm{K} \mathrm{kg}{ \mathrm{mol}}^{-1}$]