Suppose that you have a choice between going to the movies with a friend for two hours or working a part-time job. If you go to the movies, you will spend $8 on a ticket and $5 on popcorn. If you choose to work, you will earn $15 an hour. a) What is your opportunity cost of working?

For each of the following examples of data, determine which scale of measurement is used. a) the number of miles joggers run per week. b) the starting salaries of graduates of mba programs c) the months in which a firm's employees choose to take their vacations. d) the final letter grades received by students in a math course.