Answer:
∠ADB=35°
Explanation:
Given arc AB = 70°.
we have to find the angle ∠ADB
Here, Angle subtended by arc AB at O is ∠AOB = 70°
By the theorem,
The angle subtended by an arc at the center is double the angle subtended by it at any point on the remaining part of the circle.
∴ ∠AOB=2(∠ADB)
⇒

hence, angle subtended at the circumference is 35°