Calculate your opportunity cost of going to a movie premiere at the theatre with your friend Spencer on Saturday night in the following scenarios:
(a) Your neighbor is offering you $100 to baby-sit her 4-year old, and you would have to pay $10 for the movie ticket.
(b) Your neighbor is offering you $100 to baby-sit her 4-year old, and Spencer is paying for your ticket.
(c) You have no other plans for the night, and Spencer is paying for your ticket.
(d) You have already bought your $10 movie ticket, and you can resell it for $8 dollars.
(e) You have already bought your $10 movie ticket, but the showing is sold out and tickets are now selling for $30 on the black market.