Which of the following will form an ideal solution?

In a binary ideal solution of liquids $A$ and $B$ at a constant temperature,the mole fraction of $A$ in the liquid phase is $0.7$ and in the vapor phase is $0.4$. If $P_A^o + P_B^o = 90 \, mm$,then the vapor pressures of pure liquids $A$ and $B$ at that temperature are respectively:

The total pressure observed by mixing two liquids $A$ and $B$ is $350 \ mm \ Hg$ when their mole fractions are $0.7$ and $0.3$ respectively. The total pressure becomes $410 \ mm \ Hg$ if the mole fractions are changed to $0.2$ and $0.8$ respectively for $A$ and $B$. The vapour pressure of pure $A$ is $........... \ mm \ Hg$. (Nearest integer)
Consider the liquids and solutions behave ideally.

On mixing $10 \ mL$ of acetone with $40 \ mL$ of chloroform,the total volume of the solution is

What is meant by positive and negative deviations from Raoult's law and how is the sign of $\Delta_{mix} H$ related to positive and negative deviations from Raoult's law?

Which of the following pairs of liquids shows a negative deviation from Raoult's law?