(a) Find the demand for goods a and y derived from the Cobb-Douglas utility function as a result of the utility maximization problem. (Hint: The demand should be a function of income, o and its own price) (b) Find the demand for goods r and y as a result of expenditure minimization (Hicksian Demands). (c) Find the income and substitution effects of the Cobb-Douglas demand. (d) Find the own-price elasticity, the income elasticity and the cross-price elasticity