Four charges 2 C, - 3 C, - 4 C and 5 C respectively are placed at all the corners of a square. Which of the following statements is true for the point of intersection of the diagonals ?

Let l be the length of the square. The length of the diagonal will be $\sqrt{2}\mathrm{l}$. Potential at the point of intersection of diagonal $\mathrm{V}=\frac{1}{4{\mathrm{\pi \epsilon }}_0}\times \frac{(2-3-4+5)}{(\sqrt{2}\mathrm{l}/2)}=0$ and electric intensity at this point is 
$\mathrm{E}=\frac{1}{4{\mathrm{\pi \epsilon }}_0}\left[\frac{2}{{\mathrm{l}}^2/2}\mathrm{i}-\frac{3}{{\mathrm{l}}^2/2}\mathrm{j}-\frac{4}{{\mathrm{l}}^2/2}\mathrm{i}+\frac{5}{{\mathrm{l}}^2/2}\mathrm{j}\right]$
none-zero.