3. (3) A hydroelectric dam is an example of a highly efficient energy transfer process (a) Consider a 50 MW dam where the height difference between the top and bottom is 25.0 m. If the efficiency of the process of gravitational potential energy is 87%, what is the volume of water that goes through the dam per second? 4. (3) Give an order of magnitude estimate of the energy storage capacity for a typical electric car battery. State your initial assumptions