Answer:
50
Explanation:
The first thing that is important to note is that every circle's arcs equal 360. So, you find arc QS by using the equation 120+140+x=360. Once you solve this you get 100. Next, it is important to understand what type of angle R is. The angle is on the circle; this means that the corresponding arc will be double the measurement of the angle. Therefore, divide 100 by 2 and you will have the final answer of 50.