## Calculus (3rd Edition)

$f(t)= 5e^{t \ln 7}$, $P_0=5$ and $k=\ln 7$.
Using the property that $x=e^{\ln x}$, we have $$f(t)=5 (e^{\ln 7})^t=5e^{t \ln 7}.$$ Hence, $P_0=5$ and $k=\ln 7$.