The inverse of the proposition $(p \wedge \sim q) \Rightarrow r$ is

$A$ charge $q$ is placed at the centre of the line joining two equal charges $Q$. The system of the three charges will be in equilibrium if $q$ is equal to:

$A$ convex mirror of focal length $f$ forms an image which is $1/n$ times the object. The distance of the object from the mirror is

$2, 3$-dimethylhexane contains tertiary,secondary,and primary carbon atoms,respectively:

Oxalic acid reacts with concentrated $H_2SO_4$ to give a mixture of two gases. When this mixture is passed through caustic potash,one of the gases is absorbed. What is the product formed by the absorbed gas with caustic potash?

What is the mole ratio of benzene $({P_B}^0 = 150 \ torr)$ and toluene $({P_T}^0 = 50 \ torr)$ in the vapour phase if the given solution has a vapour pressure of $120 \ torr$?