A piston–cylinder assembly (see the above sketch) contains 0.006m³ air at 20 °C. The gas forces on each side of the piston, assuming there are no frictional forces at the piston–cylinder interface, balance the weight of the piston. The piston has a cross-sectional area of 100 cm² and a mass of 300 kg. The atmospheric pressure is 100 kPa, and the local gravitational acceleration is 9.8 m/s².

A. Determine the mass of air trapped within the cylinder.
B. Determine the distance the piston moves after a 600-N weight is placed on top of the piston. Assume the new equilibrium temperature is still 20 °C.
C. In what way is the gas like a mechanical spring?