Many of the pesticides for citrus trees are toxic to fish. When the citrus groves on a large farm were treated with pesticides, high winds deposited 100 gallons of pesticides into a lake stocked with fish. To ensure survival of the fish, 95% of the pesticides must be removed from the lake within 96 hours of contamination. There are two methods of removal.
A: Add a chemical reagent to the pond to neutralize the pesticide. This chemical reagent removes the pesticide at the rate of 11 gal/hr. B: Fit the pond with a filtration system. This system removes 4% of the remaining pesticides each hour. Method A sound reasonable but I am not sure and I also don't know how to create an equation for the method. Please help.