62.8 ft
Step-by-step explanation:
To find circumference we need the radius, however in the figure they gave you the diameter and the diameter is two times the radius d=2r, from the figure the diameter equals 20 so we substitute to get 20=2r, dividing both sides by two we get that r=10 ft
Now we substitute in our circumference formula C=2 πr
So C=2*3.14*10
C=62.8 ft