Which of the following solutions will show the maximum depression in freezing point when the concentration is $0.1 \, M$?

When mercuric iodide $(HgI_2)$ is added to an aqueous solution of potassium iodide $(KI)$,the

For a $0.1 \, molal$ aqueous solution of $2-$iodopropanoic acid,the degree of dissociation is $5 \%$. The freezing point of the solution will be ............ $^o C$.

Calculate the freezing point (in ${}^{\circ}C$) of a solution obtained by dissolving $0.1 \ g$ of potassium ferricyanide (molecular weight $= 329$) in $100 \ g$ of water. Given that $K_f$ for water is $1.86 \ K \ kg \ mol^{-1}$.

The freezing point (in ${}^{\circ}C$) of a solution containing $0.1 \ g$ of $K_3[Fe(CN)_6]$ (Mol. Wt. $329$) in $100 \ g$ of water $(K_f = 1.86 \ K \ kg \ mol^{-1})$ is

Molal depression constant for a solvent is $4.0 \, K \, kg \, mol^{-1}$. The depression in the freezing point of the solvent for $0.03 \, mol \, kg^{-1}$ solution of $K_2SO_4$ is .............. $K$ (Assume complete dissociation of the electrolyte).