The dimensional formula for permittivity of free space $\left({\epsilon }_0\right)$ in the equation $F=\frac{1}{4\pi {\epsilon }_0}\frac{q_1{q}_2}{r^2}$, where symbols have their usual meaning, is

From the dimensional consideration, which of the following equations is correct? (Here $T=$time period, $R=$radius, $M=$mass and $G=$gravitational constant)

$\int \frac{dx}{\sqrt{2ax-x^2}}=a^{\mathrm{n}}{\sin }^{-1}\left[\frac{x}{a}-1\right]$

Find the value of $n$. (Solve using dimensional analysis)