So if the die has six sides 1,2,3,4,5, and 6 then there are three even numbers in that number set. Three is half of 6 so you will have half the chance of rolling an even number
The 1.8 s is the time for the signal to reach the ocean floor and return to the ship so the time to reach ocean floor = 1.8 / 2 = 0.90 seconds. depth of ocean = speed * time
