A gas expands at constant temperature from an initial volume of 0.040 m3 and an initial pressure of 210 kPa until its pressure drops to 135 kPa. How much work is done by the system

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.