As the fish-and-game warden of your township, you are responsible for stocking the town pond with fish before fishing season. the average depth of the pond is 20 feet. you plan to start the season with one fish per 1000 cubic feet. you intend to have at least 25% of the opening day's fish population left at the end of the season. what is the maximum number of licenses the town can sell if the average seasonal catch is 20 fish per license?