Answer:
113.1
Step-by-step explanation:
Write down the equations on the top of your paper; it could help you throughout your homework.
The equation for circumference is 2 times pi, times the radius.
The Radius is the diameter times two.
2 times 9=18, so therefore the radius is 18.
Once you have that done, just put in your calculator 2 times pi times 18.