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3. Suppose the demand function for a firm's product is given by the following: Q*d = 20 - 1.5Px + 2Py -2.5Pz + 6Income Where, Px = $10 Py = $8 Pz = $5 Income = $10,000 Show work. a) Given the above prices, what is the quantity purchased? b) Determine the own-price elasticity of good x. c) Is demand elastic, inelastic or unit elastic? d) If the price of good x increased by 10%, what would be the change in sales? e) Determine the cross-price elasticity of demand between good x and good y