7.5*(2.54/2)^2*3.14=37.98
37.98*0.3=11.39
37.98*0.4=15.19
37.98*0.5=18.99
37.98*0.6=22.79
37.98*0.7=26.59
37.98*0.8=30.38
37.98*0.9=34.18
37.98*1=37.98