If ethanol dissolves in water,then which of the following would be done?

An aqueous solution freezes at $-0.186 \ ^\circ C$ ($K_f = 1.86 \ ^\circ C \ kg \ mol^{-1}$; $K_b = 0.512 \ ^\circ C \ kg \ mol^{-1}$). What is the elevation in boiling point of the same solution?

$A$ non-volatile solute is dissolved in water. The $\Delta T_b$ of the resultant solution is $0.052 \ K$. What is the freezing point of the solution (in $K$)?
($K_b$ of water $= 0.52 \ K \ kg \ mol^{-1}$; $K_f$ of water $= 1.86 \ K \ kg \ mol^{-1}$,Freezing point of water $= 273 \ K$)

If the mole fraction of the solvent decreases while preparing a solution,then ...........

Solid Lead nitrate is dissolved in $1 \, L$ of water. The solution was found to boil at $100.15^{\circ}C$. When $0.2 \, mol$ of $NaCl$ is added to the resulting solution,it was observed that the solution froze at $-0.8^{\circ}C$. The solubility product of $PbCl_2$ formed is $........... \times 10^{-6}$ at $298 \, K$. (Nearest integer) Given: $K_b = 0.5 \, K \, kg \, mol^{-1}$ and $K_f = 1.8 \, K \, kg \, mol^{-1}$. Assume molality to be equal to molarity in all cases.

$6 \ g$ of a mixture of naphthalene $(C_{10}H_8)$ and anthracene $(C_{14}H_{10})$ is dissolved in $300 \ g$ of benzene. If the depression in freezing point is $0.70 \ K$,the composition of naphthalene and anthracene in the mixture respectively in $g$ are (molal depression constant of benzene is $5.1 \ K \ kg \ mol^{-1}$)