8. Assume an individual has preferences represented by the utilityr function U (x, y) = it}? + y. Which of the following statements is necessarily true, assuming an interior solution? a. The price consumption curve {as the price of )1 changes} slopes downward. b. The income consumption curve slopes downward. c. Cross-price elasticity of demand for good it with respect to the price of y is negative. d. Price elasticity of demand for good 3? is positive