Which solution has the maximum boiling point?

Which one of the following $0.06 \ M$ aqueous solutions has the lowest freezing point?

Two solutions of $KNO_3$ and $CH_3COOH$ are prepared separately. Molarity of both is $0.1 \ M$ and osmotic pressures are $P_1$ and $P_2$ respectively. The correct relationship between the osmotic pressures is :-

The addition of a polar solvent to a solid electrolyte results in

$AB_2$ is $10\%$ dissociated in water to $A^{2+}$ and $B^{-}$. The boiling point of a $10.0 \text{ molal}$ aqueous solution of $AB_2$ is . . . . . . $^\circ C$. (Round off to the Nearest Integer). [Given: Molal elevation constant of water $K_b = 0.5 \text{ K kg mol}^{-1}$,boiling point of pure water $= 100^\circ C$]

The $\Delta T_{b}$ value for $0.01 \ m$ $KCl$ solution is $0.01 \ K$. What is the Van't Hoff factor? $(K_{b}$ for water $= 0.52 \ K \ kg \ mol^{-1})$