An ideal gas at 27 °C has an initial pressure of 1.5 × 10⁵ Pa and volume of 2.4 L. It is first compressed isothermally to a volume of 0.8 L. The gas is then allowed to expand isothermally until its pressure becomes 2.25 × 10⁵ Pa. What is the final volume of the gas?
a) 1.2 L
b) 2.4 L
c) 1.6 L
d) 0.8 L