30) UAF =

\(\angle UAF = \angle ZAF - \angle ZAU\)

\(\angle ZAU\) = 180° - \(\angle ZAB\) - \(\angle BAU\) = 180° - 50° = 130°

\(\angle ZAF\) = 180° - \(\angle ZAB\) - \(\angle BAF\) = 180° - 20° = 160°

\(\angle UAF\) = 160° - 130° = 30°

Ответ: 30°