A capacitor is a device used in a variety of electronic circuits. In a simple design a capacitor consists of two parallel metal plates of area A separated by a distance d. When the plates are connected to the positive and negative terminals of a battery, electrons are pulled off one plate leaving it positively charged and transferred to the other plate, leaving this plate negatively charged. The capacity, C, of a parallel-plate capacitor is given by C = ?o A / d where ?o is the permittivity of free space. The charge, Q, stored on a capacitor (+Q on one plate and –Q on the other) connected to a potential difference V is given by Q = C V The energy stored in a capacitor is given by E = ½ Q V A parallel-plate capacitor is connected to a battery. What happens if the plate separation is doubled while the capacitor remains connected to the battery? A) The stored energy is decreased by a factor of four. B) The stored energy is quadrupled. C) The stored energy is doubled D) The stored energy remains the same E) The stored energy is decreases by a factor of two