Three would be your answer :)
The volume of a cylinder is
V=hpr^2 in this case h=40, r=20/2=10, and we will approximate pi as 3.14 so:
V=40(3.14)(10^2)
V=12560 ft^3
What the size of the border is. Example. You want to fence your yard. What do you do. Measure the perimeter aka the border.
