An ideal gas undergoes a cycle process as shown in figure

$\Delta {\cup }_{BC}=-5kJmo{l}^{-1},q_{{ }_{AB}}=2kJmo{l}^{-1};w_{AB}=-5kJmo{l}^{-1},W_{CA}=3kjmo{l}^{-1}$

Heat absorbed by the system during process CA is:

$\begin{array}{l}\Delta {\cup }_{{ }_{BA}}=q_{{ }_{AB}}+w_{{ }_{AB}=2+(-5)=-3kJ/mol}\\ \Delta {\cup }_{{ }_{BC}=-5kJ/mol}\end{array}$

For cyclic process, $\Delta \cup =0$

$$\begin{gathered} \Delta {\cup }_{{ }_{AB}}+\Delta {\cup }_{{ }_{BC}}+\Delta {\cup }_{{ }_{CA}}=0 \\ \Delta {\cup }_{{ }_{CA}}=-(-3)-(-5)=8kJ/mol \\ \Delta {\cup }_{{ }_{CA}}=q_{{ }_{CA}}+w_{{ }_{CA}} \\ 8=q_{{ }_{CA}}+3\Rightarrow q_{{ }_{CA}}=5kJ/mol \end{gathered}$$

Heat absorbed has positive sign.