Here are some guides that Atlanta Sewer is providing pertaining to plumbing math volume help:
Finding the volume of a rectangular tank
Formula V = L x W x H
Finding the volume of a cylindrical tankV = D x D x 0.7854 x L or V = ∏R2L
Finding the volume of an elliptical tankV = H x W x 0.7854 x L
Finding the volume of a spherical tank