Answer
$V_3 = 5.00~V$
Work Step by Step
In part (e), we found that the potential difference across $C_2$ is $10.0~V$
Since $C_3$ and $C_5$ are in parallel with $C_2$, then $V_2 = V_3+V_5$
Since $C_3 = C_5$, then by symmetry, $V_3 = V_5$
Therefore, $V_3 = 5.00~V$
