For, assume complete dissociation
For $\mathrm{Na}_{2} \mathrm{SO}_{4} ; \quad i=3, m=0.01$
$\begin{aligned}
&\Delta T_{b}=i K_{b} m \\
&\Delta T_{b}=3 \times K_{b} \times 0.01=0.03 K_{b}
\end{aligned}$
For, 0.01 M $\mathrm{KNO}_{3}$;
$\begin{aligned}
i &=2, m=0.01 \\
\Delta T_{b} &=2 \times K_{b} \times 0.01 K_{b}=0.02 K_{b}
\end{aligned}$
While, urea and glucose are non-electrolyte They do not dissociate into ions highest boiling point is shown by $0.01 \mathrm{M} \mathrm{Na}_{2} \mathrm{SO}_{4}(a q)$ solution.