Answer:
B) 20 degrees
Step-by-step explanation:
Arc length = fraction of the circle * circumference
Arc length = fraction of the circle * 2 * pi *r
pi = fraction of the circle * 2 * pi *9
pi = fraction of the circle *18 pi
Divide each side by 18pi
pi
-------- = fraction of a circle
18 pi
1/18 = fraction of a circle
A circle is 360 degrees
1/18 = x/360
Multiply by 360 on each side
360/18 = x
20=x