From the problem, the diameter of the sphere is 20 ft.
Note that radius is half of diameter, so the radius will be r = 20/2 = 10 ft
Using the volume formula of a sphere.
[tex]V=\frac{4}{3}\pi r^3[/tex]
where π = 3
[tex]\begin{gathered} V=\frac{4}{3}(3)(10)^3 \\ V=4000 \end{gathered}[/tex]
The answer is 4000 ft^3
