Answer:
arc BC = 140
Explanation:
Comment
Pick a point inside the circle. It should look like this point is the center of the circle. Call this point D. Draw lines CD and BD
CD makes a right angle with AC
BD makes a right angle with AB
The central angle formed by The given information above is
<BDC = 360 - 90 - 90 - 40
<BDC = 140.
Answer The arc measurement of BC = 140