Amanda draws $\overline{PQ}$ with endpoints $P(3,-2)$ and $Q(2,8)$. She then draws $\overline{PR}$ so that it is perpendicular to $\overline{PQ}$.

What is the slope of $\overline{PR}$?
A. $10$
B. $-{\frac{1}{10}}$
C. $-10$
D. ${\frac{1}{10}}$