The demand for Good X is given by Qx = 4000-Px-2Py+4Pz +0.2M where Py is the price of good Y, Pz is the price of good Z, and M is income, if Py =$800, Pz = $200 and M= $5000 determines the following:
1. The inverse demand function for good X.
2. Whether good Y is a substitute or complement for good X. explain why.
3. Whether good Z is a substitute or complement for good X. explain why
4. Whether good X is a normal or inferior good. Explain why