A large brine tank containing a solution of salt and water is being diluted with fresh water.
The relationship between the elapsed time, t, in hours, after the dilution begins, and the concentration of
salt in the tank, S(t), in grams per liter (g/l), is modeled by the following function.
S(t) = 600.e-0.31
How many hours will it take for the concentration of salt to decrease to 100 g/l?
Round your answer, if necessary, to the nearest hundredth.
hours