Pump Problem: Flow Rate and Elevation Calculation

Ethylbenzene at 40 degrees C is delivered by a pump from a storage tank to a reactor elevated 3.5 m above the pump.  The pressure at the inlet to the reactor is 1.5 barg.  There is a control valve in the line, with a pressure drop of 0.75 bar across it.  the flowrate of ethylbenzene is 8 L/s. What is the maximum flowrate possible with the valve fully open?  If the tank is open to the atmosphere, what is the minimum required elevation of liquid in the tank? The tank is at atmospheric pressure.  Please explain the procedure used to solve the problem in detail.