Volume of a frustum of a cone
$$V = \frac{1}{3}\cdot \pi\cdot h\cdot (R^{2}+r^{2}+R\cdot r)$$
V - volume
R - radius of lower base
r - radius of upper base
h - height of a frustum of a cone
R - radius of lower base
r - radius of upper base
h - height of a frustum of a cone
Find
It is known that:
= 