1. The problem statement, all variables and given/known data Consider the solid obtained by rotating the region bounded by the given curves about y=10 Find the volume V of this solid using DISK METHOD 2. Relevant equations y=5e^-x, y=5, x=4 3. The attempt at a solution setting up the picture easy. but i'm having trouble knowing HOW to find the radius. any help would be cool. thank you.