Which pair from the following will not form an ideal solution?

$5$ moles of liquid $X$ and $10$ moles of liquid $Y$ make a solution having a vapour pressure of $70 \ torr$. The vapour pressures of pure $X$ and $Y$ are $63 \ torr$ and $78 \ torr$ respectively. Which of the following is true regarding the described solution?

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?

Two liquids $A$ and $B$ have vapour pressure in the ratio $P_A^o : P_B^o = 1 : 3$ at a certain temperature. Assume $A$ and $B$ form an ideal solution and the ratio of mole fractions of $A$ to $B$ in the vapour phase is $4 : 3$. Then the mole fraction of $B$ in the solution at the same temperature is

Assertion $A$: For an ideal solution formed by mixing liquids $P$ and $Q$, $\Delta_{mix} H = 0$ and $\Delta_{mix} V = 0$.
Reason $R$: No interactions occur between $P$ and $Q$.
In the light of the above statements, choose the most appropriate answer from the options given below:

What is a non-ideal solution and what is meant by positive deviation from Raoult's law?