Consider the stirred-tank heater shown in Figure II.3. The steam is injected directly in the liquid. A1 is the cross-sectional area of the tank.Assume that the effluent flow rate is proportional to the liquid static pressure that causes its flow. 1. Identify the state variables of the system. 2. Determine what balances you should perform. 3. Develop the state model that describes the dynamic behavior of the system.