The doorbell rang and Jack went to answer it. He opened the door. A UPS guy was there. "Is your parents there," he asked. "No," Jack replied, "they are out of town for the weekend." "Well, here you go. Be very careful with it. It is fragile." Jack received the package wondering what is inside. Maybe it is a bomb. Jack opened it anyway. Inside there was fifty different vials. Two of one kind. They were labled by letters. There were no instruction. Jack decided to try one labbled A. And...