Suppose you want to remove a thousand fish of an exotic species that have been illegally introduced to a lake (e.g., piranha). You have three possible removal methods. Assume that Q1, Q2, and Q3 are, respectively, the amount of fish removed by each method that you choose to use so that the goal will be accomplished by any combination of methods such that Q1 +Q2 +Q3 = 1000. (a) If the marginal costs of each removal method are, respectively, 20Q1, 10Q2, and 5Q3, how much of each method should you use to achieve the removal cost-effectively? (b) Why isn’t an exclusive use of method 3 cost effective?