Answer: 27.42 ft
Explanation:
To find the perimeter first we must find the circumference of the circles.
You can easily find the diameter by subtracting and you get 6.
Using the circle circumference formula c=2piR you get 9.42.
9.42 is our circumference of one circle.
You don't need to divide this by 2 because you already have 2 halves of a circle.
Next add all the sides which is 18.
Add this to the circumference we calculated earlier which gives you 27.42 ft.