[30 POINTS) 3. A power plant produces 620 MW of electricity with 38% efficiency by burning natural gas, which has an energy content of 50,000 kJ/kg. Transmission lines convey this energy with 92% efficiency to a home, where a microwave oven consuming 1 kW is 47% efficient at converting electrical energy to heat in the food. a. How many joules of heat are produced in the power plant for each joule of heat given to the food? b. When the microwave is on, at what rate (in g/s) is natural gas being burned to supply it