2 points A piston moves down a cylinder so that the enclosed mass of air expands whilst the temperature remains constant. Given that the initial pressure and volume are 10 bar and 0.42m, respectively, and that the final pressure is 2 bar, find the work done. W=75.9kJ W=675.9kJ OW= -67.9kJ W=-675.9kJ OW=67.9kJ