posted by chelsea .
Initially 1.200 mol of an ideal gas in a container occupies a volume of 3.50 l at a pressure of 3.30 atm with an internal energy U1 = 547.2 J. The gas is cooled at a constant volume until its pressure is 1.80 atm. Then it is allowed to expand at constant pressure until its volume is 7.90 l. The final internal energy is U2 = 673.7 J. All processes are quasi static. What is the work done by the gas?