Answer:
 115°
Explanation:
A kite is symmetrical about the long diagonal, so the angles at the ends of the short diagonal are congruent. The given angles, X and Z, are not congruent, so are at the ends of the long diagonal. The remaining two angles, W and Y, are congruent, and bring the total of all angles to 360°.
 90° +40° +2W = 360°
 2W = 230° . . . . . . . . . subtract 130°
 m∠W = 115°