Suppose a country's population in 1980 was 210 million. in 1990 it was 225 million. using the exponential growth formula, p = ae^kt, estimate the country's population in 2000. before you can estimate the population p in 2000, you'll need to find a, t, and k. start by finding a. remember, a is the population at time t = 0. the value of a stays the same throughout a given problem. if t = 0 in 1980, find the value of a. round your answer to the nearest million.