A piston-cylinder device initially contains steam at 200 kPa, 200° C, and 0.4 m³. At this state, a linear spring (Fa x) is touching the piston but exerts no force

on it. Heat is now slowly transferred to the steam, causing the pressure and the volume to rise to 250 kPa and 0.6 m³, respectively. Determine the total heat transferred in kJ.