A hydroelectric power facility converts the gravitational potential energy of water behind a dam to electric energy. (For each answer, enter a number.)

(a)What is the gravitational potential energy (in J) relative to the generators of a lake of volume 21.0 km³ (mass = 2.10 10¹³ kg), given that the lake has an average height of 36.0 m above the generators? J

(b)Compare this with the energy stored in a 9-megaton fusion bomb.E_lake/E_bomb =