One mole of an ideal gas is contained in a cylinder with a movable piston. The initial pressure, volume, and temperature are Pi, Vi, and Ti, respectively. Find the work done on the gas for the following processes and show each process on a PV diagram: (a) An isobaric compression in which the final volume is half the initial volume. (b) An isothermal compression in which the final pressure is four times the initial pressure. (c) An is volumetric process in which the final pressure is three times the initial pressure