An ideal gas undergoes a cyclic  process  as shown in fig
     

$△U_{BC}=-5kJmo{l}^{-1},q_{AB}=2kJmo{l}^{-1}$
$W_{AB}=-5kJmo{l}^{-1},W_{CA}=3kJmo{l}^{-1}$
Heat absorbed by the system during process CA is ;

$△U_{AB}=q_{AB}+W_{AB}=2+(-5)=-3kJ/mol$

$△U_{BC}=-5kJ/mol$

For cyclic process,  $△U=0$
$△U_{AB}+△U_{BC}+△U_{CA}=0$
$△U_{CA}=-△U_{AB}-△U_{BC}$
$△U_{CA}=-(-3)-(-5)=8kJ/mol\frac{\pi }{6}$
$△U_{CA}=q_{CA}+W_{CA}$
$8=q_{CA}+3\Rightarrow q_{CA}=+5kJ/mol$
Heat absorbed has positive sign