An equilateral triangle `A B C` is inscribed in a circle with centre `Odot` The measures of `/_B O C` is `30^@` (b) `60^@` (c) `90^@` (d) `120^@`

Explanation

To solve the problem, we need to find the measure of angle \( \angle BOC \) in the context of an equilateral triangle \( ABC \) inscribed in a circle with center \( O \).

### Step-by-Step Solution:

1. **Understand the Properties of the Equilateral Triangle**:
- In an equilateral triangle, all sides are equal, and all angles are equal to \( 60^\circ \).
- Therefore, \( \angle A = \angle B = \angle C = 60^\circ \).

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