Answer:
9ft
Step-by-step explanation:
The base area of the storage is its volume divided by height
[tex]A = \frac{V}{h} = \frac{607.5}{7.5} = 81 ft^2[/tex]
Since this base is a square, its length and width is of equal length, which is
[tex]\sqrt{A} = \sqrt{81} = 9ft[/tex]
