After a 200 pF capacitor is charged to a potential difference of 40 V, the battery is removed. Then the charged capacitor is connected in parallel with another uncharged capacitor. If the potential difference across the charged capacitor now drops to 30 V, determine (i) the capacitance of the uncharged capacitor and (4 marks) (ii) the energy stored in the uncharged capacitor. (2 marks)