The angle subtended by an arc at the center is half of the angle subtended by the arc at any point on the remaining part of the circle.
O is the centre of the circle. AB is a minor arc of the circle. The angle subtended by AB at centre ∠AOB = 110∘, then angle subtended by the arc at any point on the remaining part of the circle i.e. ∠APB is (where P is any point on the circle)?