Economics Question 3 (75 marks) a) Given the inverse demand function Q, = 50 -2PA - 3Pg + 0.5Y, where Q, is the quantity of good A, P. is the price of good A, P, is the price of an alternate good B, and Y is income, calculate: i) the own-price elasticity of demand il) the cross-price elasticity of demand ill) the income elasticity of demand H where PA = 5, Pp = 10, and Y = 20. Comment on the economic significance in each case. [30 marks]