Hello!
To find the volume of a cone you use the equation
[tex]V = \pi r^{2} \frac{h}{3} [/tex]
V is volume
r is radius which is half the diameter
h is height
Put in the values you know and 3.14 for pi[tex]V = 3.14 * 10^{2} * \frac{26}{3} [/tex]
Multiply
V = 2721.3333
The answer is 2721.3 cubic feet
Hope this helps!