Answer
$ a.\quad 1\%$ increase in population per year
$ b.\quad\approx 69$ years
Work Step by Step
$ a.$
Model: $ A=A_{0}e^{kt}.$
Here, $ k=0.01$, which represents a $1\%$ increase in population per year.
$ b.$
Use the formula for time needed to double the population:
$ t=\displaystyle \frac{\ln 2}{k}$=$\displaystyle \frac{\ln 2}{0.01}\approx 69$ years
