I am trying to put the answer 256 for this but I am getting it wrong I need help understanding why.

Given:
The diameter of the sphere is 8cm.
To find:
The volume of the sphere.
Explanation:
The radius of the sphere is,
[tex]\begin{gathered} r=\frac{d}{2} \\ =\frac{8}{2} \\ r=4cm \end{gathered}[/tex]Then, the volume formula of the sphere is,
[tex]V=\frac{4}{3}\pi r^3[/tex]Plug in the value of radius for r, and we get
[tex]V=\frac{4}{3}\times3\times[4]^3[/tex]Evaluating the value we get,
[tex]\begin{gathered} V=4\times4^3 \\ V=256cm^3 \end{gathered}[/tex]Final answer:
• The value that goes into the green box is 4.
,• The volume of the sphere is 256 cubic cm.