A gold mine has two elevators, one for equipment and another for the miners. The equipment elevator descends 5 feet per second. The elevator for the miners descends 15 feet per
second. One day, the equipment elevator begins to descend. After 23 seconds, the elevator for the
miners begins to descend. What is the position of each elevator relative to the surface after
another 18 seconds? At that time, which elevator is deeper?