If you have more than one question, you need to make separate posts.

To determine the annual growth rate, you need to determine how much the population increases in a single year.

The exponential growth formula is

`A=A_0 b^t` where A is the final amount, `A_0` is the initial amount,...

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If you have more than one question, you need to make separate posts.

To determine the annual growth rate, you need to determine how much the population increases in a single year.

The exponential growth formula is

`A=A_0 b^t` where A is the final amount, `A_0` is the initial amount, b=1+r is the base, r is the growth rate and t is the time in years. In this case, we are told that after 15 years, we have the population doubled, which means that when t=15, `A=2A_0` . Then:

`2A_0=A_0 b^15` divide by `A_0`

`2=b^15` take 15th root

`2^{1/15}=b` but b=1+r

`2^{1/15}=1+r` solve for r

`r=2^{1/15}-1`

`r approx 0.0473`

**The annual growth rate is approximately 4.73%.**