1A 5-kg piston in a cylinder with a diameter of100 mm is loaded with a linear spring and the outside atmospheric pressure is 100 kPa, as shown in Fig. PI.101.

The spring exerts no force on the pis-ton when it is at the bottom of the cylinder, and for the state shown, the pressure is 400 kPa with volume 0,4 L The valve is opened to let some air in, causing the piston to rise 2 cm. Find the new pressure.