A perfect gas (0.1 mol) having $$\bar{C}_v = 1.50 R$$ (independent of temperature) undergoes the transformation from point 1 to point 4 as shown in the P-V diagram. If each step is reversible, the total work done (w) while going from point 1 to point 4 is $$(-) \text{____}$$ J (nearest integer).
[Given: $$R = 0.082$$ L atm $$K^{-1} mol^{-1}$$]