Show in a diagram the effect on the demand curve, the supply curve, the equilibrium price, and the equilibrium quantity of each of the following…

     Show in a diagram the effect on the demand curve, the supply curve, the equilibrium price, and the equilibrium quantity of each of the following events.

The market for the Krugman and Wells economics textbook

Case 1: Your professor makes it required reading for all of his or her students.

Case 2: Printing costs for textbooks are lowered by the use of synthetic paper.