***

Correct answers will receive 1 mark.  Incorrect answers will

receive -0.75 mark.  An answer left blank will receive 0 marks.  So decide

carefully before you answer.***

Suppose Kristin wants a doughnut from Tim Hortons, however when she gets close she sees that the line up is really long, so she decides not to stop.  For Kristin this means that the marginal cost of her time waiting in line plus the cost of the doughnut exceeds the marginal benefit of eating the doughnut.