An ideal gas undergoes a cyclic process as shown in Figure

Heat absorbed by the system during the process CA is

 
$\Delta U_{BC}=-5kJmo{l}^{-1}$ 
$q_{AB}=2kJmo{l}^{-1}$ 
$W_{AB}=-5kJmo{l}^{-1}$ 
$W_{CA}=3kJmo{l}^{-1}$