According to the following graph, the price of Y is $50.

a. What is the consumer's income? (3')

b. If the relevant budget line is MF, what is the price of X? (3')

c. Write the equation for the budget line MF. (3')

d. If the relevant budget line is MF, what combination of X and Y will the consumer choose? Why? (3')

e. What is the marginal rate of substitution at this combination of question d? (3')