Answer
$\left|V_{\text {center }}\right|=7.8 \times 10^4 \mathrm{~V}$.
Work Step by Step
The value at $r=0$ is
$$
\left.V_{\text {center }}=\frac{-1.1 \times 10^{-3} \mathrm{C} / \mathrm{m}^3}{4\left(8.85 \times 10^{-12} \mathrm{C} / \mathrm{V} \cdot \mathrm{m}\right)^{(l)}} d 0.05 \mathrm{~m} \mathrm{l}^2-0\right\\=-7.8 \times 10^4 \mathrm{~V} .
$$
Thus, the difference is $\left|V_{\text {center }}\right|=7.8 \times 10^4 \mathrm{~V}$.
