Which from the following liquid mixtures behaves nearly as an ideal solution?

At a particular temperature,the vapour pressures of two liquids $A$ and $B$ are respectively $120 \, mm$ and $180 \, mm$ of mercury. If $2 \, moles$ of $A$ and $3 \, moles$ of $B$ are mixed to form an ideal solution,the vapour pressure of the solution at the same temperature will be (in $mm$ of mercury):

Liquids $A$ and $B$ form an ideal solution. The vapour pressure of pure $A$ and $B$ are $50 \ mm \ Hg$ and $32 \ mm \ Hg$ respectively at $300 \ K$. One mole of liquid $A$ is mixed with $1$ mole of liquid $B$. What is the approximate mole fraction of $A$ in the vapour phase?

An aqueous solution of hydrochloric acid:

In a mixture of $A$ and $B$ components,the solution shows negative deviation when:

Which of the following liquid mixtures shows a positive deviation from Raoult's law?