(c) In steady state current drawn from the battery
$i = \frac{E}{(R_{2} + r)}$
In steady state capacitor is fully charged hence No current will flow through line (2)
Hence potential difference across line (1) is $V = \frac{E}{(R_{2} + r)} \times R_{2},$ the same potential difference appears across the capacitor, so charge on capacitor
$Q = C \times \frac{ER_{2}}{(R_{2} + r)}$