c) Use a graphical analysis (nullclines) to determine how many equilibrium points this system has and say as much as you can about where they occur in the state space. What can you say about the stability of each equi librium point? (Hint: It is possible to do this without having to plug in any numbers for the parameters, assuming only that the parameters are all positive numbers. However, you may plug in reasonable numbers for them if you wish. The nullclines should look roughly the same regardless of what numbers you use.) Also, all but one of the equilibrium points are easy to compute algebraically by hand, but unfortunately this "hard\" one is the most interesting