II.1 Consider the two systems shown in Figure PII.1. System 1 differs from system 2 by the fact that the level of liquid in tank 2 does not affect the effluent flow rate from tank 1 , which is the case for system 2. (a) Develop the mathematical model for each of the two systems. (b) What are the state variables for each system, and what type of balance equations have you used? (c) Which mathematical model is easier to solve, that for system 1 or that for system 2? Why? Assume that the flow rate of an effluent stream from a tank is proportional to the hydrostatic liquid pressure that causes the flow of liquid. The cross-sectional area of tank 1 is A1(ft2) and of tank 2 is A2(ft2)(for both systems). The flow rates F1,F2, and F3 are in ft3/min. Figure PII.1