Answer:



Step-by-step explanation:
The volume of the cylinder is

where r is the radius of a base circle and h is the cylinder's height.
If cylinder has diameter of 8 inches, then its radius is 4 inches. The height of the cylinder is 5 inches. Thus, the volume of the cylinder is

The volume of the cone is

where r is the radius of a base circle and h is the cone's height.
If cone has diameter of 8 inches, then its radius is 4 inches. The height of the cone is 15 inches. Thus, the volume of the cone is

As you can see the cylinder and the cone have the same volume.
The side length is about 17.916
What do you mean? I think you need to add a graph with the angles for people to be able to answer that question (you can take a screenshot and then use the paperclip button when you are re-writing the question). Hope this helped.