t2 4 A population grows at a rate P'(t) = 200te[ ] , where P(t) is the population after t months. a. Find a formula for the population size aftert months, given that the population is 4000 at t= 0. 13. Use the answer from part a to nd the size of the population after 7 months. (I) a. Find a formula for the population size aftert months, given that the population is 4000 at t= 0. P(t) = E (Type an exact answer in terms of e.) b. The size of the population after 7 months is about D. (Round to the nearest person as needed.)