Coefficient of performance triangle process thermodynamics

[viniterranova]

Homework Statement

An ideal gas adiabatic coefficient γ is submitted to the ABCA cycle of fig, where AB is a line segment..
a) Calculate the income.
b) Show that it is smaller than the yield of a Carnot cycle operating between the same temperature extremes.

this is my attempt.

Homework Equations

P=nRT/V

The Attempt at a Solution

 

[TSny]

Your result for the work done in the cycle looks correct.

In the next line you have calculated some heat Q. Please explain what heat this represents and how you got this result.