Aparallel-plate capacitor is made of two conducting plates of area a separated by a distance d. the capacitor carries a charge q and is initially connected to a battery that maintains a constant potential difference between the plates. the battery is then disconnected from the plates and the separation between the plates is doubled. (1) which of the following remains constant? (a) voltage across the capacitor (b) capacitance of the capacitor (c) charge on the capacitor (2) briefly explain your answer to the previous question. (3) the electric potential energy stored in the capacitor will: (a) stay the same (b) increase (c) decrease (4) briefly explain your answer to the previous question.