Logistic growth: $P(t)=\frac{C}{1+a e^{-k t}}$
For populations that exhibit logistic growth, the population at time $t$ is modeled by the function shown, where $C$ is the carrying capacity of the population (the maximum population that can be supported over a long period of time), $k$ is the growth constant, and $a=\frac{c-P(0)}{P(0)} .$ Solve the formula for $t$, then use the result to find the value of $t$ given $C=450, a=8, P=400,$ and $k=0.075$.