For spherical symmetrical charge distribution, variation of electric potential with distance from center is given in diagram. Given that $V=\frac{q}{4\pi {\epsilon }_0{R}_0}$ for $r\le R_0$ and $V=\frac{q}{4\pi {\epsilon }_{0}r}$ for $r\ge R_0$

Then which option(s) is/are correct

The given graph is of charged conducting sphere of radius $R_0$. The entire charge distributes on the surface of the sphere.

$$\begin{gathered} E = 0 for 0\le r<R and E = \frac{Q}{4\mathrm{\pi }{\in }_0{\mathrm{r}}^2} R\le r \\ Electrostatic energy U = \frac{1}{2}{\in }_0{E}^2 and so u =0 where E = 0 .For a charged metalliv shell , \\ electric field is zero inside the shell. \end{gathered}$$