For question a) Can you draw the simple sketch in the paper with input output values.

Also, for question b) what are the inflow and outflow variables?

and for the unknown are there only one unknown which is the concentration of PCB in the river after mixing? or have two unknowns which are total flow rate after mixing and concentration of PCB in the river after mixing?

Also, is the answer to question e) determined? or the other?

Thank you

a) Draw a simple sketch describing the process. b) Write the inflow and outflow variables and their values (if known) and units. c) Identify the unknowns. d) Write down the material balance equation for each specie. e) Check the formulated math model. If it is i. Determined, solve for the unknowns ii. Under determined, find additional constraints (equations) iii. Over determined, eliminate incorrect, irrelevant, or least important constraints 4. A plant discharges 4000gal/min of treated wastewater that contains 0.25mg/L of PCBs (polychloronated biphenyls) into a river that contains no measurable PCBs upstream of the discharge. If the river flow rate is 1500ft3/s, after the discharged water has thoroughly mixed with the river water, what is the concentration of PCBs in the river in milligrams per liter