The 2000 U. S. Census reports the populations of Bozeman, Montana, as 27,509 and Butte, Montana, as 32,370. Since the 1990 census, Bozeman’s population has been increasing at approximately 1.96% per year. Butte’s population has been decreasing at approximately 0.29% per year. Assume that the growth and decay rates stay constant. Determine the exponential functions that model the populations of both cities.