A cylinder fitted with a piston containing 1kg of Refrigerant 134a at 20C and 90% vapor quality is attached to a line flowing Refrigerant 134a. The total force on the piston is proportional to the cylinder volume squared. The valve is now opened and Refrigerant 134a flows into the cylinder until the mass inside is three times the initial mass and the final pressure in the assembly is 900 kPa at which point the valve is closed. Determine the work done during this process, in kJ.