Mark has preferences represented by a utility function U(x1,x2) = x11/3x22/3. The prices of x1 (cookies) and x2 (soda) are p1 and p2, respectively. Income is equal to Y. Answer the following:
What kind of utility does Mark have? Write Mark's budget constraint and an equality you can use to find Mark's optimal demand choice for cookies and soda.
Derive Mark's demand function for cookies. Are cookies a normal or an inferior good for Mark?