At each of the points \((5, 5, \frac{\pi}{2}\), (\pi, \pi, \pi), (-3, 3, \frac{\pi}{6})\), evaluate the function \(w(r, s, t) = \frac{r-t}{\sin(t)}\) or indicate that the function is undefined there.
(Use symbolic notation and fractions where needed. If the function is undefined at the given point, type UNDEFINED.)
\(w(5, 5, \frac{\pi}{2}) = \)
\(w(\pi, \pi, \pi) = \)
\(w(-3, 3, \frac{\pi}{6}) = \)
