Answer 1

120°

Explanation;

Hint:

Since PR is tangent of the circle.

∠QPR = 90°

∠OPQ = 90° – 60° = 30°

∠OQB = 30°

In ∆OPQ

∠P + ∠Q + ∠O = 180°

30 + 30° + ∠O = 180°  ...(OP and OQ are equal radius)

∠O = 180° – 60° = 120°