QUESTION 7 A coalfired power station is a huge heat engine. It uses heat transfer from burning coal to do work to turn turbines, which are used to generate electricity. In a single day, a large coal power station has 6.04X1014J of heat transfer from coal and 2.3ZX1O14J of heat transfer into the environment. What is the work done by the power station? Input your answer in J using exponent notation with 3 signicant gure. : 11 points Save Answer QUESTION 8 A coalfired power station is a huge heat engine. It uses heat transfer from burning coal to do work to turn turbines, which are used to generate electricity. In a single day, a large coal power station has 7.24x1014J of heat transfer from coal and 2.15x1014J of heat transfer into the environment. What is the efficiency of the power station? Input your answer with 3 signicant gure. 11 points Save Answer QUESTION 9 A power reactor has pressurized water at 326C . Steam, produced in the steam generator, is used to drive the turbine-generators. Eventually the steam is condensed to water at 32C and then heated again to start the cycle over. Calculate the maximum theoretical efciency for a heat engine operating between these two temperatures. E 11 points Save Answer QUESTION 5 What is the change in internal energy of a system which does 12.3>