You go to an "all-you-can-eat" buffet. If you maximize utility, the marginal utility of the last bite that you eat will be

You go to an "all-you-can-eat" buffet. If you maximize utility, the marginal utility of the last bite that you eat will be
a. equal to the price of the buffet
b. as high as possible
c. zero
d. dependent on how much you like the buffet

my answer is A

Suzy knows she has maximized her utility, because she is on her budget constraint and
a. consumption of good X equals consumption of good Y
b. what is spent on good X equals what is spent on good Y
c. MUx/Px = MUy/Py
d. MUx = MUy

My answer is c

Benny spends all his money buying wine and cheese. The marginal utility of the last bottle of wine is 60, and the marginal utility of the last block of cheese is 30. The price of wine is $3, and the price of cheese is $2. Benny
a. is buying wine and cheese in the utility-maximizing amounts
b. should buy more wine and less cheese
c. should buy more cheese and less wine
d. is spending too much money on wine and cheese