First, we find arc RSP
[tex]\begin{gathered} 108=\frac{1}{2}\cdot RSP \\ \text{RSP}=2\cdot108=216 \end{gathered}[/tex]Arc RSP measures 216°.
Then,
[tex]\begin{gathered} 216+RQP=360 \\ \text{RQP}=360-216=144 \end{gathered}[/tex]Now, we find angle S
[tex]m\angle S=\frac{1}{2}\cdot144=72[/tex]