Kids trade items in the school lunchroom. It is very difficult to find a pair of kids who each wants the others' food among hundreds of kids. So, the kids start trading their food away for YumPops (a popular snack that everyone will accept), and then trading the YumPops to other kids for the food they want. Since YumPops go bad after a couple hours, all are consumed by the end of the day. In this case, YumPops are serving the role of Instructions: Check the box for all correct answers. Uncheck the box for any incorrect answers. There may be more than one correct answer. O Medium of Exchange O The Stockmarket O Unit of Account O Store of Value
