$2.($b$)$ Let $p,a,r$ and $s$ be the $S$ tatements. "The weather is warm". "The sky is clear", $"$we go swimming" and $"$me go boating" respectively. Sy molize the following argument and prove its validity by using a inference thuory:

If the sky is dear, then either we go swimming on we go boating.

The sky is clear and we do notgo swimming. Therefore, we goboating.