Three CSTRs are used in series. The second reactor has a volume twice that of the first and third reactors. The influent flow has a concentration of 150 mg/l of A, and the flowrate is 380 l/min. The reaction is first order, the rate equation is -dCa/dt= KCa= -ra and the rate constant is 0.4/hr. Determine:

a) A graph of -ra on the y-axis versus Ca on the x-axis on arithmetic paprr.
b) The mean residence time and volume of each reactor if the removal or conversion of A is 90%. What are the concentrations of A and the rate of conversion in each reactor? Use a graphic solution using the graph from part(a). Express volume as litres.