Consider the demand function for a good given as Qd = 150 + 4I - 0.2P2 - 5P1 where income I is in $1,000 and P1 is the price of a related good.
(a) What is the relationship between these two goods?
(b) calculate the income, cross price, and own price elasticity of demand if I = $ 45,000, P1 = $30, and P = $25.
(c) At what price demand is own price unit elastic if income is $40,000 and P1 is $35?