A horizontally positioned cylinder containing 1 mol of gas at an initial temperature T₀ and pressure P₀ is closed by a piston of section S. To the right of the piston is a constant atmospheric pressure P₀. The gas is heated by a spiral. When the piston moves, it is affected by the friction force F from the cylinder walls. Half of the heat generated when the piston rubs against the cylinder walls goes to the gas. The internal energy of the gas is U = cT. How does the temperature of a gas depend on the amount of heat transferred to the gas by the spiral? Plot this relationship.