D) estimate when the population will reach 500,000.This is the question I am struggling with

This exercise uses the population growth model. The population of a certain city was 145,000 in 2006, and the observed doubling time for the population is 19 years. (a) Find an exponential model n(t) = no2t/a for the population t years after 2006. n(t) = 145000 2 19 (b) Find an exponential model n(t) = noert for the population t years after 2006. (Round your r value to four decimal places.) n(t) = 145000-0.0365t (c) Sketch a graph of the population at time t. n(t n(t) 700 000 700 000 600 000 600 000 500 000 500 000 400 000 400 000 300 000 300 000 200 000 200 000 100 000 100 000 - t O 10 20 30 40 10 20 30 40 n(t) n(t) 700 000 700 000 600 000 600 000 500 000 500 000