When mercuric iodide is added to the aqueous solution of potassium iodide

Some of the following are true solutions:
I: Air
II: Seawater
III: Glucose solution
IV: Gemstone
V: Pearl
VI: Blood
Select true solutions:

$1.00 \mathrm{g}$ of a non-electrolyte solute (molar mass $\left.250 \mathrm{g} {\mathrm{mol}}^{-1}\right)$ was dissolved in $51.2 \mathrm{g}$ of benzene. If the freezing point depression constant, ${\mathrm{K}}_{\mathrm{f}}$ of benzene is $5.12 \mathrm{K} \mathrm{kg} {\mathrm{mol}}^{-1},$ the freezing point of benzene will be lowered by