Answer:
52°
Step-by-step explanation:
Angle AOB is the a.pex angle of the isosceles triangle AOB.* Then angles at A and B are congruent and each is the complement of half the angle at O:
∠OAB = 90° -(1/2)(76°) = 90° -38°
∠OAB = 52°
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* You know ΔAOB is isosceles because OA and OB are both radii of the circle, hence the same length.