$[$Q$5]($a$)$ Draw an 'open$-$cycle gas$-$turbine engine' without considering the Air$-$Standard assumption.

$($b$)$ Draw the T$-$s diagram of a 'Brayton cycle with regeneration'. What's the highest possible temperature in the regenerator? What is 'effectiveness'?

$($c$).$ What will happen if you use 'petrol in diesel engine' and 'diesel in petrol engine'?

$($d$)$ Draw ACTUAL P$-v$ diagram of a petrol engine?

$15$ points