1.  Dad’s Wallet and the ATM:  Dad went to the ATM on Wednesday of spring break and withdrew some money.  On Thursday morning my brother borrowed half of Dad’s money to open a cheking account because he was always short of money.  On Friday I needed some money for a date, so I borrowed half of what remained.  My sister came along next and borrowed half of the remaining money.  Dad then went to gas up the car and used half of the rest of his money, and he wondered why he had only $15 left.  How much money did he start with in his wallet?

2.  Crossing the River with Pets:  The five family members and their five dogs (each family member owned one of the dogs) were hiking when they encountered a river to cross. They rented a boat that could hold three living things: people or dogs. Unfortunately, the dogs were temperamental. Each was comfortable only with its owner and could not be near another person, not even momentarily, unless its owner was present. Dogs could be with other dogs, however. The crossing would have been impossible except that Lisa's dog had attended a first-rate obedience school and knew how to operate the boat. No other dogs were that well educated. How was the crossing arranged, and how many trips did it take?