Use the value 3.14 for it, and round your answer to the nearest whole number:

The volume of a cylinder is given by
[tex]V=\text{ ( Area of the circle)}\times height[/tex]In our case, the area of the circle is given by
[tex]\begin{gathered} A=\pi\cdot r^2 \\ A=(3.14)(2^2) \\ A=12.56ft^2 \end{gathered}[/tex]Since the height is equal to 21 ft, the volume is given by
[tex]\begin{gathered} V=(12.56)\times21 \\ V=263.76ft^3 \end{gathered}[/tex]Therefore, by rounding this result to the nearest whole, the answer is: 264 cubic feet