Part a: Assume that the height of your cylinder is 4 inches. Consider A as a function of r, so we can write that as A(r)=2r2+8r. What is the domain of A(r)? In other words, for which values of r is A(r) defined?

Part b: Continue to assume that the height of your cylinder is 4 inches. Write the radius r as a function of A. This is the inverse function to A(r), i.e to turn A as a function of r into. r as a function of A.

Part c: If the surface area is 200 square inches, then what is the rardius r? In other words, evaluate r(200). Round your answer to 2 decimal places.