Many colleges sell special cards that students can use to purchase everything from textbooks or meals in the cafeteria to use of washing machines in the dorm. Students deposit money in their cards; as they use their cards for purchases, electronic scanners remove money from the cards. To replenish a card's money, a student makes a cash deposit that is credited to the card. Would these cards count as part of the money supply? This question is already answered here but one answer says yes and another says no. Which is corret?