What is the relation between the vapour pressure of the solution,the vapour pressure of the pure solvent,and its mole fraction in the solution?

Which of the following solutions in water will have the lowest vapour pressure?

Mass of Urea $(NH_2CONH_2)$ required to be dissolved in $1000 \ g$ of water to reduce the vapour pressure of water by $25 \ \%$ is $...... \ g$. (Nearest integer) Given: Molar mass of $N, C, O$ and $H$ are $14, 12, 16$ and $1 \ g \ mol^{-1}$ respectively.

$651 \ g$ of ethylene glycol $(HOCH_2CH_2OH)$ is dissolved in $1.5 \ kg$ of water at $363 \ K$. The vapour pressure of pure water at $363 \ K$ is $0.7 \ atm$. Assuming ideal solution behaviour,the vapour pressure of water over the solution (in $atm$) is closest to $...$

$A$ solution is prepared by mixing $8.5 \ g$ of $CH_2Cl_2$ and $11.95 \ g$ of $CHCl_3$. If the vapour pressures of pure $CH_2Cl_2$ and $CHCl_3$ at $298 \ K$ are $415 \ mm \ Hg$ and $200 \ mm \ Hg$ respectively,the mole fraction of $CHCl_3$ in the vapour phase is: (Molar mass of $Cl = 35.5 \ g \ mol^{-1}$)

What weight of glucose must be dissolved in $100 \ g$ of water to lower the vapour pressure by $0.20 \ mm \ Hg$ (in $g$)? (Assume dilute solution is being formed) Given: Vapour pressure of pure water is $54.2 \ mm \ Hg$ at room temperature. Molar mass of glucose is $180 \ g \ mol^{-1}$