Which of the following will have the lowest vapour pressure?

Which solution has the highest vapour pressure?

At a given temperature,the vapour pressure of a solution of two volatile liquids $A$ and $B$ is given by the equation $P_S = 120 - 80 \, X_B$ (where $X_B$ is the mole fraction of $B$). The vapour pressures of pure $A$ and $B$ at the same temperature are respectively:

At $80\,^{\circ}C$,the vapour pressure of pure liquid '$A$' is $520\, mm\, Hg$ and that of pure liquid '$B$' is $1000\, mm\, Hg$. If a mixture solution of '$A$' and '$B$' boils at $80\,^{\circ}C$ and $1\, atm$ pressure,then the amount of '$A$' in the mixture is ......... $mol\, \%$. $(1\, atm = 760\, mm\, Hg)$

$18 \ g$ of glucose is dissolved in $90 \ g$ of water. The relative lowering of vapour pressure of the solution is equal to

The vapour pressure of $30 \%$ $(w/v)$ aqueous solution of glucose is $...... \ mm \ Hg$ at $25^{\circ} \ C$. [Given : The density of $30 \%$ $(w/v)$ aqueous solution of glucose is $1.2 \ g \ cm^{-3}$ and vapour pressure of pure water is $24 \ mm \ Hg$.] (Molar mass of glucose is $180 \ g \ mol^{-1}$.)