$($b$)$ Assume that we are interested in the evolution of all the system variables w$1,$ w$2$ and F$.$ Consider F as input, and the remaining variables as outputs. Write an i$/$o model and a corresponding polynomial representation for the model.$($c$)$ Now assume that someone is interested in the evolution of only two of the variables, F and w$2.$ Consider F as the input and w$2$ as the output variable. Eliminate w$1$ between the two system differential equations and form an i$/$o model for the system. Then write a corresponding polynomial representation for the system.