Consider a completely-mixed tank (CSTR) where a reactive substance (Toxicrud) has a first- order decay rate of 3.2 hr". The tank dimensions are 8 ft deep by 12 ft square (width and length), with one foot of freeboard (i.e., reactor is filled to 7 ft depth). The flow rate through the reactor is 100 GPM (gallons per minute). The input concentration has been 500 mg-l' for a long time, and has reached steady state. At time t 0, the input concentration of Toxicrud is increased to 1500 mg/l. Determine the following: a) The steady state concentration of Toxicrud in the reactor for input concentration of 500 mg r'. b) The analytical solution for concentration of Toxicrud vs. time following the increase in input concentration. To find this you will need to solve this problem under non-steady conditions. Show your work! Hint: an integrating factor will help you solve this problem. c) Plot the concentration of Toxicrud versus time.