Part a: Assume that the height of your cylinder is 6 inches. Consider A as a function of r, so we can

write that as A (r) = 2 \pi r² 12 \pi r. 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 6 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 325 square inches, then what is the radius r? In other words, evaluate

r (325). Round your answer to 2 decimal places.