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