Each interior angle of a regular pentagon is 108^°, so ÐSRQ=108^°. As SR=QR, the triangle is isosceles with ÐRQS=ÐRSQ = Ð36. Similarly, ÐSRT = ÐSTR = 36^°. So ÐSUR=(180-2×36)^°=108^°. From the symmetry of the figure, ÐPUR=ÐPUS = (360^° - 108^°)/2 = 126^°.