The volume of a cone is the interesting
[tex]V = \dfrac{\pi r^2 h}{3}[/tex]
which is one third the cylinder of the same height and radius.
We have r=11 and h=84=3(28) so
[tex]V = \dfrac{\pi 11^2 (84)}{3} = 121(28)\pi = 3388 \pi \textrm { cubic units} [/tex]
Choice B
