I am studying Brayton cycle. In Brayton cycle, heat addition and exhaust is carried out at constant pressure. Now, the efficiency is $$\eta=\frac {w_{net}}{q_{in}}$$ My book, while calculating $w_{net}$ for efficiency takes into account only the compressor work and the turbine work. My doubt is shouldn't the work in constant pressure heat addition and extraction be also taken into account.
I have added the image of book problem. The book is Engineering Thermodynamics by Cengel Boles. It is an example problem. In (c) part I have to calculate efficiency. Just have a look at it.