An ideal gas undergoes a reversible process in which the pressure varies linearly with volume. The conditions at the start (subscript 1) and at the end (subscript 2) of the process with usual notation are: p₁ = 100 kPa, V₁ = 0.2 m³ and p₂ = 200 kPa, V₂ = 0.1 m3 and the gas constant, R = 0.275 kJ/kgK. The magnitude of the work required for the process (in kJ) is______.