so we know the radius of the sphere is 8, and its surface area is 4πr², therefore its surface area is 4π8², namely 256π.
we also know that the surface area of the cylinder is half that of the sphere, namely 256π/2 or 128π, let's use that surface area to get the height h.

since now we know h and r for the cylinder, and we also know r for the sphere, let's check their volume's ratio.
