it has a,b and c sections

The organ shown below is controlled by a proportional controller. A liquid carries a drug into an organ of volume Vcm3 at a rate q1cm3/min and also water added at a rate of 1cm3/min and leaves at a rate 1 cm3/min. (Assume; outlet flow=inlet flow) The concentration of drug in the solution leaving the organ is controlled by adding a concentrated drug through a control valve. The following data apply: 1. Concentration of concentrated drug solution C1=25g drug / cm3 solution. 3. Control valve: The flow through the control valve varies from 0.002 to 0.0006ft/min with a change of valve-top pressure from 3 to 15 psi. This relationship is linear. 4. Distance velocity lag: It takes 1min for the solution leaving the tank to reach the concentration-measuring element at the end of the pipe. 5. Neglect lags in the valve