G8.1 If $\log _{9} S=\frac{3}{2}$, find $S$.
G8.2 If the lines $x+5 y=0$ and $T x-S y=0$ are perpendicular to each other, find $T$.
$\begin{array}{l}S=9^{3 / 2}=27 \\ -\frac{1}{5} \times \frac{T}{27}=-1 \\ T=135\end{array}$