To answer this item, we assume that the air is an ideal gas, such that it behaves following the ideal gas law,
PV = nRT
If all else are equal in two systems, comparison of the relationship of the volume and pressure becomes,
P₁V₁ = P₂V₂
Substituting the known values in the equation,
(203 kPa)(0.5 L) = (50.8 kPa)(V₂)
The value of V₂ from the equation is 1.998 L or 2 L.
Hence, the answer is the third choice, 2.0 L.