To find a volume of a cylinder you use the formula pi r^2 h. You have h=18.75 but are missing r. To find r you make a right triangle. Then use A^2 +b^2=c^2; where a =18.75 b=diameter, and c=21.25. After solving you get the diameter equals 10. Now cut that in half to get the radius =5. Now you can use the volume equation. Plugging in you have pi*(5)^2*18.75. This will give you 1472.62m^3