(b) Work done(W)=$- p_{ext}(V_{2} - V_{1})$ $= - 3 \times (6 - 4) = - 6\ L\ atm$ $\ = \ - 6 \times 101.32$ J($\therefore$ 1 L atm=101.32 J) $= \ - 607.92 \approx - 608\ J$
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.