A gas is enclosed in a cylinder fitted with a movable piston. The cylinder has a circular cross-section with diameter $20.0\,\text{cm}$. The gas pressure is $102\,\text{Pa}$, and at the start the piston is $30.0\,\text{cm}$ above the cylinder base. When the gas is heated, the piston rises until it is $35.0\,\text{cm}$ above the base. Throughout this change, the pressure stays constant. What amount of work is done by the gas in moving the piston?
- A$0.160\,\text{J}$
- B$0.641\,\text{J}$
- C$1.12\,\text{J}$
- D$4.49\,\text{J}$