Algae is being grown in a tank to be dried out and used as fish food. The algae is being harvested so that its intrinsic growth rate is r = -0.08 (grams/day)/gram. Let W(t) be the weight of the algae in the tank after t days. (a) What is the rate equation satisfied by W(t)? (b) To keep the population of algae from dying out, the tank is stocked at a constant rate of 40 grams/day. What is the new rate equation for W? (c) What are the equilibrium points of the new equation? (d) Classify the stability of the equilibrium points.
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