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The circumstances surrounding the George Reserve in Michigan have made it particularly easy for ecologists to monitor accurately the growth of the deer population on the reserve. They have developed the logistic function Macmillan Learning 6.21 N = 0.035 + 0.45' to model the population. Here, N denotes the number of deer and t denotes the time, in years, since observation began. According to this model, when will the deer population reach 140? (Use decimal notation. Give your answer to two decimal places.) 1 = years