please solve it ( thermodynamics 1 )

Solve the following problems and show the details of your calculations: Air contained within a vertical piston-cylinder assembly is shown below. On its top, the 10kg piston is attached to a spring and exposed to an atmospheric pressure of 1 bar. Initially, the bottom of the piston is at x=0, and the spring exerts a negligible force on the piston. The valve is opened and air enters the cylinder from the supply line, causing the volume of the air within the cylinder to increase by 0.00039m3. The force exerted by the spring as the air expands within the cylinder varies linearly with x according to [Fspring=kx], where k=10,000N/m. The piston face area is 0.0078m2. Ignoring friction between the piston and the cylinder wall, determine the pressure of the air within the cylinder, in bar, when the piston is in its initial position. Repeat when the piston is in its final position. Take g=9.81m/s2