If e-the initial hight of the tree, and the function imply some brackets like
f(x)=30/(1+29e-0.5x) then
for every
[tex]0.5x > 29e + 1[/tex]
the rate of growth is negative, the maximum growth per unit of time would be 30ft
If
[tex]x \geqslant 1[/tex]
then
[tex]29e < - 0.5[/tex]
so the tree couldn't be 2ft tall initially
if the brackets are something like
f(x)=30:(1+29e)-0.5x then the results may differ