Use the following general linear demand relation to answer questions 4 through 8: Qa = 250 - 3P - 0.002M + 4PR where P is the price of good X, M is income, and PR is the price of a related good, R. 4. Is good X normal or inferior? (5pts) 5. Is the related good R a substitute for good X or a complement for good X? (5pts) 6. What is the demand function when M= $50,000 and PR = $7? Show your work. (5pts) 7. If M= $50,000 and PR = $7, and the supply function is Q, = 26 + 5, what is the market price and what is the market output? Show your work (5pts) 8. If the government sets the price at $20, will that result in a surplus or a shortage? What will be the size (in units) of the surplus or shortage? Show your work. (5pts)