Math Help - Trig and exponentials

1. Trig and exponentials

The population of town A is double that of town B but is decreasing at a rate of 5% per year. The population of town B is increasing by 5% per year.
a)In how many years will the population of town B be double the amount of town A?

please show all work and calculations. Thanks

2. Since A=2B, we can set up two equations, equate and solve for t.

$2e^{-.05t}=e^{.05t}$

Solve for t.