The formula is:
V = π(r^2)h/3
Since this problem gives you the diameter and not the radius, I would take half of the diameter because a radius is half of a diameter.
The half of 8 is 4, so the radius is 4
V = π(4^2)(9/3)
V = π(4^2)(3)
V = π(16)(3)
V is about 150.8
