Sharifah has the following utility function:
U(X,Y) = √X + √Y where X is her consumption of brownies (pastry), with price PX=$1, and Y is her consumption
of espressos (coffee), with PY=$3. Assume that she has a budget I=$100.
a. Using the method of Lagrange multipliers to derive Sharifah's demand for brownies and espressos. Explain how many brownies and espressos will Sharifah consume? (Partial quantities are possible.)
b. What is the marginal utility of income?