Circle theorems II — practice question

This diagram depicts a circle with eight chords. The angles marked are $20^{\circ}$ and $72^{\circ}$ at the upper-right point on the circumference, $56^{\circ}$ at an internal intersection, $u^{\circ}$ at the lower-right point, $w^{\circ}$ at the lowest point, and $x^{\circ}$ and $v^{\circ}$ at the left point.