Originally Posted by

**alakaboom1** This problem has me extremely confused, would really appreciate some help..

A right circular cone and a hemisphere have the same base, and the cone is inscribed in the hemisphere. The figure is expanding in such a way that the combined surface area of the hemisphere and its base is increasing at a constant rate of 18 square inches per second. At what rate is the volume of the cone changing at the instan when the radius of the common base is 4 inches?

As i said, im extremely confused and have nothing....Thanks in anyone can help!!