blood1221 blood1221 03-11-2021 Physics contestada A warm cup of coffee has 20 000 J of energy. After being heated in a microwave, the cup of coffee has 70 000 J of energy. How much work was done by the microwave to heat the coffee? (a) 20 000 J (b) 50 000 J (c) 70 000 J (d) 90 000 J