The population of a colony of rabbits grows exponentially. The colony begins with 5 rabbits; 5 years later there are 360 rabbits.

(a) Express the population of the colony of rabbits, $P$, as a function of time, $t$, in years.
$P(t) =$

(b) Use the graph to estimate how long it takes for the population of rabbits to reach 1000 rabbits.
It will take years. (round to nearest 0.01 year)