Economics question

4. (20 points) Emma Emma loves playing with action figures (a) and Legos ((). Her preferences can be represented by the following utility function: u(a, l) = al The prices of the action figures are Pa > 0, legos pe > 0, and her income is I > 0. (a) (10 points) Find the demand function for good action figures as a function of prices and income./ (b) (5 points) Identify the substitution and income effect for the demand for action figures. (c) (5 points) Calculate the own-price elasticity of the demand for action figures