In a lightning storm, the potential difference between the Earth and the bottom of the thunderclouds can have a high value like 30,000,000 V. Consider the bottom of the cloud and the Earth's surface as a huge capapcitor. If the bottom of the thundercloud is 1500 m above the Earth, and has an area of 95 km2, calculate:
(a) the capacitance of the Earth-cloud system
(b) the charge stored in the "capacitor"
(c) the energy stored in the "capacitor"