[Single-digit Integer] The final volume (in L) of one mole of an ideal gas initially at 27°C and 8.2 — Thermodynamics and Thermochemistry Chemistry Question

Question

[Single-digit Integer] The final volume (in L) of one mole of an ideal gas initially at 27°C and 8.21 atm pressure, if it absorbs 420 cal of heat during a reversible isothermal expansion, is