process control. please help

Example 3.3 Level in a Tank Problem Statement. Develop a dynamic model of a level in the tank shown in Figure 3.5.9. The process parameters and variables are given by - Ae - cross-sectional area of the tank(0.3m2) - L - the level of liquid in the tank (initially 2 meters) - Fin - the mass flow rate of liquid into the tank (1.0kg/s) - Few- - the mass flow rate of liquid leaving the tank (initially 1.0kg/s ) - t - time (s) - - the fluid density (1kg/l) - , - the time constant for the control valve on Fout(5s). Figure 3.5.9 Schematic of a level in a tank At time equal to 10 seconds, the specified value of Fout is process. changed from 1.0 to 0.9kg/s. The dynamics of the level sensor are assumed instantaneous