At the freezing point of a solution containing a nonvolatile solute,which of the following are in equilibrium?

Given below are two statements $:$
Statement $(I) : NaCl$ is added to the ice at $0^{\circ} C$,present in the ice cream box to lower the freezing point of the mixture,which helps in keeping the ice cream frozen.
Statement $(II) :$ On addition of $NaCl$ to ice at $0^{\circ} C$,there is a depression in freezing point.
In the light of the above statements,choose the correct answer from the options given below $:$

When $36 \ g$ of a non-volatile,non-electrolytic solute having the empirical formula $CH_2O$ is dissolved in $1.2 \ kg$ of water,the solution freezes at $-0.93 \ ^\circ C$. The molecular formula of the solute is ($K_f$ of water $= 1.86 \ K \ kg \ mol^{-1}$)

If molality of the dilute solution is doubled,the value of molal depression constant $(K_f)$ will be

$A$ solution containing $8.0 \, g$ of nicotine in $92 \, g$ of water freezes $0.925 \, ^{\circ}C$ below the normal freezing point of water. If the molal freezing point depression constant,$k_f = 1.85 \, ^{\circ}C \, kg \, mol^{-1}$,then the molar mass of nicotine is $...$

$A$ solvent freezes at $17^{\circ} C$ and it has a latent heat of fusion of $180 \ J \ g^{-1}$. The molal depression constant $(K_{f})$ of the solvent is (in $K \ kg \ mol^{-1}$):