Hoover Dam produces electricity for residents of Nevada, Arizona, and California. The dam is 200 meters tall. Lake Mead sits at the top of the dam and contains about 10 billion cubic meters of water. Estimate how much gravitational potential energy is stored with the dam at any given time. In other words, how much gravitational potential energy would be lost if all of the water went during the dam? (A cubic meter of water has a mass of 1000 kilograms.)