20 pi
Circumference is Diameterpi so if it uses that either use 3.14 to substitute for pi or use the real number.
20 pi
Okay, so do 20pi and what you get from that is 62.8318530718(that's as far as my calculator goes...)
If you want to use 3.14 you get 62.8. So in reality it's 20 pi.
