The height of a sand dune (in centimeters) is represented by $f(t) = 600 - 7 t^2$ cm, where $t$ is measured in years since $1995$. Find $f(4)$ and $f'(4)$, and determine what each means in terms of the sand dune. Give the values of $f(4)$ and $f'(4)$ below, including units.

$f(4) =$
$f'(4) =$