We are asked to determine the volume of a sphere. To do that we will use the following formula:

Where "r" is the radius.
We are given that the diameter is 8cm. We have that:

Where "D" is the diameter. This means that the radius is half the diameter. Substituting we get:
![r=\frac{8\operatorname{cm}}{2}=4\operatorname{cm}]()
Now we substitute in the formula for the volume:
![V=(4)/(3)\pi(4\operatorname{cm})^3]()
we will use:

Substituting we get:
![V=(4)/(3)(3)(4\operatorname{cm})^3]()
Now we solve the operations:-
![V=4(4\operatorname{cm})^3=256\operatorname{cm}^3]()
Therefore, the volume of the sphere is 256 cubic centimeters.