Please help me

1.The surface are of the exterior of hollow rubber ball is 16pi in^2.The rubber is 1/4 inch thick. Find the surface are of the interior of the ball.

2. The length of each side of a cube is 6 inches long. Find the exact area of a sphere inscribed in the cube.

1 answer

evidently r=4
so, the inside radius is 3.75
The inside area is 4pi * 3.75^2

The inscribed sphere has a diameter of 6, and a radius of 3.
v = 4/3 pi r^3
plug and chug

also, the length is not six inches long. Each side is six inches long; the length is just six inches.