+1521 Let M, N, and P be the midpoints of sides \overline{TU}, \overline{US}, and \overline{ST} of triangle STU, respectively. Let \overline{UZ} be an altitude of the triangle. If \angle TSU = 70^\circ, \angle STU = 30^\circ, and \angle TUS = 70^\circ, then what is \angle NSZ + \angle NUZ in degrees?
