A Sonar of a ship sends sounds waves of speed 1500 m/s. These waves are reflected back by the ocean floor in 5 seconds. Find the depth (in m) of the ocean floor.
Alarms from 3 different clocks sound after every 2, 4 and 6 hours, respectively. If the clocks are startedat the same 6 time, how many times do the alarms ring together in 3 days?