Given a right cylinder with height $2r$ and radius $r$, define a function $f(r)$ representing the ratio of the surface area to the volume. What is the simplified form of the function?
a) $f(r) = {3/2}$
b) $f(r) = {4/r}$
c) $f(r) = {2/r}$
d) $f(r) = {1/2r}$