Diameter is 9 inch so the radius is 9/2=4.5inch Part A: 2πr=28.26inch π=28.26/(2r) π=28.26/(2*4.5)=3.14 Part B: πr^2=63.585inch π=63.585inch/(4.5inch)^2 π=3.139753086 Part C: Both of the answers are correct but Part B is more percise because it has more significant figures.