Given $\Delta T_{f}=2.8, K_{f}=1.86 \,K \mathrm{kg} \mathrm{mol}^{-1} i=1$
(ethylene glygol is a non-electrolyte)
wt. of solvent $=1\, \mathrm{kg}$
Let of wt of solute $=x$
Mol. wt of ethyllene glycol $=62$
$2.8=1 \times 1.86 \times \frac{x}{62 \times 1}$
or $\quad x=\frac{2.8 \times 62}{1.86}=93 \,gm$