Which one has the highest boiling point?

The elevation in boiling point of a solution of $13.44 \ g$ of $CuCl_2$ in $1 \ kg$ of water using the following information will be (Molecular weight of $CuCl_2 = 134.4 \ g \ mol^{-1}$ and $K_b = 0.52 \ K \ kg \ mol^{-1}$)

The freezing point of an equimolal aqueous solution will be highest for:

$A$ sample of water is found to contain $5.85 \% \left(\frac{w}{w}\right)$ of $AB$ (molecular mass $58.5$) and $9.50 \% \left(\frac{w}{w}\right)$ $XY_2$ (molecular mass $95$). Assuming $80 \%$ ionisation of $AB$ and $60 \%$ ionisation of $XY_2$, the freezing point of the water sample is: [Given, $K_f$ for water $= 1.86 \ K \ kg \ mol^{-1}$, freezing point of pure water $= 273 \ K$ and $A, B, X, Y$ are monovalent ions.] (in $K$)

Maximum depression in freezing point is caused by

In a $0.2 \ molal$ aqueous solution of a weak acid $HX$,the degree of ionisation is $0.25$. The freezing point of the solution will be nearest to ......... $^oC$. $(K_f = 1.86 \ K \ kg \ mol^{-1})$