During 21 weeks at the height of an influenza outbreak, the rate at which the number of cases of infection changed could be approximated by I'(t) = -6.54t+ 142.2, where I is the total number of infected people and t is time measured in weeks. Answer parts a) through d). a) Estimate I(t), the total number of people who have contracted influenza by time t. Assume that I(0) = 1399. 1(t) = -3.27t + 142.2t+1399 b) Approximately how many people contracted influenza during the first 8 weeks? 2327 people (Round to the nearest integer as needed.)