When a solution containing a non-volatile solute freezes,which equilibrium exists?

Ethylene glycol is used as an antifreeze in cold climates. To prevent $4 \ kg$ of water from freezing at $-6^{\circ}C$,how many grams of ethylene glycol must be added? (Given for water: $K_f = 1.86 \ K \ kg \ mol^{-1}$,Molar mass of ethylene glycol $= 62 \ g \ mol^{-1}$)

Elements $X$ and $Y$ form two non-volatile compounds ($XY$ and $XY_3$). When $10 \ g$ of $XY$ is dissolved in $50 \ g$ of ethanol,the depression in freezing point $(\Delta T_{f})$ is $5.333 \ K$. When $10 \ g$ of $XY_3$ is dissolved in $50 \ g$ of ethanol,the $\Delta T_{f}$ is $2.2857 \ K$. What are the atomic weights of $X$ and $Y$ respectively? $(K_{f} = 2 \ K \ kg \ mol^{-1})$

What is the cryoscopic constant of water if $5 \ g$ of glucose in $100 \ g$ of water causes a depression in freezing point of $2.15 \ K$? (Molar mass of glucose $= 180 \ g \ mol^{-1}$)

What is the depression of freezing point,when mole fraction of non-electrolyte solute in aqueous solution is $0.01$ (in $K$)? ($K_f$ of $H_2O = 1.86 \ K \ kg \ mol^{-1}$)

The freezing point of a solution containing $4.8 \ g$ of a compound in $60 \ g$ of benzene is $4.48 ^\circ C$. What is the molar mass of the compound $(K_f = 5.1 \ K \ kg \ mol^{-1})$,(freezing point of benzene $= 5.5 ^\circ C$)?