If the price of one good goes up and the demand of a related good goes down, the two goods are

Vicky currently produces at point a in the figure above. If Vicky moves from point a to point b to point c, her opportunity cost of a modem ________

A) decreases B) increases C) is zero D) remains the same

Joe quits his job as an insurance agent and opens his own sporting goods store. If his profits as measured by his accountant are greater than zero, then

A) he made a good move because he is earning above normal profits. B) his economic profit must be greater than zero. C) his opportunity costs must be zero. D) There is not enough information to determine his economic profit, if any.