Answer:
∠ ACE = 40°
Explanation:
The sum of the angles in a circle = 360°, thus
arc AE = 360° - (112 + 28 + 112)° = 360° - 252° = 108°
∠ ACE is half the difference of the intercepted arcs, that is
∠ ACE = 0.5( arc AE - arc BD) = 0.5(108 - 28)° = 0.5 × 80° = 40°