100 yards * 36 = 3600 inches.
3600*1.257*10^-19 = 4523.9*10^-19 or 4.523*10^-16in^3
A cylinder volume is base times height, or an area of the circle times the other dimension. 4/2^2 is 4pi (12.57), and the yards have to be converted to inches. Check out my steps and see where you went wrong.