2p + 100 M , where p is the price of yo-yos and M is income. (a) What is the income elasticity of demand for yo-yos? (b) What is the price elasticity of demand for yo-yos? 15.8 (0) If the demand function for zarfs is P = 10 (a) At what price will total revenue realized from their sale be at a maximum? (b) How many zarfs will be sold at that price?