Recall the stirred-tank heating process with variable holdup as described in Section 2.4.2. Recalculate the degrees of freedom for this example under the following separate circumstances (be sure to explain clearly your outputs, manipulated inputs, and disturbance inputs):
(a) The flow rate exiting the tank is through an orifice, and the overall rate is dictated by hydrostatic forces.
(b) Two feedback controllers are added to the system, one adjusting the heating rate (Q) as a function of the temperature of the tank, and the other adjusting the exit flow rate (w) as a function of the volume of the tank.