3. An invasive fish, species I, is thriving and growing at 10% per year after 20 individuals are introduced to the lake. The native fish in the same ecological niche, species N, drops from 440 individuals when the invasive species was introduced to 400 individuals two years later. Let P(t) = I(t) + N(t) be the total population of the invasive and native fish species. (a) Find exponential models I(t) and N(t) that represent the invasive and native species' populations, respectively, t years after the invasive species came to the lake. Then find a formula for the total population of invasive and native fish P(t). (b) Determine the time intervals where P(t) is concave up. (c) Determine and identify all absolute max and min values