A shallow lake can be considered a CFSTR. Nitrification, the conversion of ammonia to nitrate (NH3 -> NO3-) occurs in the lake according to first - order kinetics. One stream feeds the lake and one stream empties the lake with the flow rate in both being 8 cfs. If the first - order decay coefficient is 0.02 day-1, the influent ammonia concentration is 3.5 mg/L and effluent ammonia concentration is 0.25 mg/L, what is the volume of the lake in cubic feet?