A12.5μf capacitor is connected to a power supply that keeps a constant potential difference of 24.0 v across the plates. a piece of material having a dielectric constant of 3.75 is placed between the plates, completely filling the space between them. a.) how much energy is stored in the capacitor before the dielectric is inserted? b.) how much energy is stored in the capacitor after the dielectric is inserted? c.) by how much did the energy change during the insertion? did it increase or decrease? d.) explain why inserting the dielectric (or equivalently exchanging air with the material) causes a change in the stored energy of the capacitor.