An ideal gas expands at a constant total pressure of 3.4 atm from 410 ml to 750 ml. Heat then flows out of the gas at constant volume, and the pressure and temperature are allowed to drop until the temperature reaches its original value. Calculate the total work done by the gas in the process.
a) 285.6 J
b) 856.8 J
c) 428.4 J
d) 570.2 J