A piston-cylinder arrangement contains water (50 kg) at 150 kPa and 25C. The cylinder's diameter is 36 cm. Heating begins: the water partially transforms into steam, and there is an expansion (the piston can move). When the volume reaches 0.2 m, the piston hits a spring with a spring constant of 100 kN/m. Heating continues, and the piston moves another 20 cm.

a) Find the final pressure and final temperature.

b) Find the work done. Draw a P-V diagram."