An ideal parallel-plate capacitor with plate area \(A\) and plate separation \(d\) is connected to a battery that maintains a constant potential difference \(V_0\), establishing a capacitance \(C_0\) and an electric field magnitude \(E_0\) between the plates. The capacitor is modified by doubling the plate area to \(2A\) and halving the separation distance to \(d/2\) while remaining connected to the battery. What are the new capacitance \(C'\) and the new electric field magnitude \(E'\) between the plates?