Answer:
Angle BOC = 120°
Angle DOC = 60°
Angle ODC = 90°
Explanation:
Triangle ABC is an equilateral triangle, therefore Angle BAC = 60°.
Now that we know Angle BAC, we can find Angle BOC: 2 × 60 = 120°
Angle DOC = ½ Angle BOC ( Radius drawn from centre to midpoint of chord, bisect the angle)
So Angle DOC = ½ (120) = 60°
Angle = 90° because D is the midpoint of chord BD and OD is a radius.