Solution :
As, all sides are of same length (4 ft.) of this rectangular solid.
Therefore, it is a square.
Now, we have a formula to find volume of square :
[tex] \large \underline{\boxed{\sf{ Volume = side^{3} }}}[/tex]
[tex] \sf : \implies Volume = (4 \: ft.)^{3}[/tex]
[tex] \sf : \implies Volume = 4 \times 4 \times 4 \: ft.^{3}[/tex]
[tex] \sf : \implies Volume = 64 \: ft.^{3}[/tex]
[tex] \large \underline{\boxed{\sf{ Volume = 64 \: ft.^{3} }}}[/tex]
