Which data is used to make a sonar map of the ocean floor?

Question

the amount of spreading that occurs on the ocean floor
the time it takes an underwater vehicle to reach the ocean floor
the amount of light that reaches the ocean floor
the time it takes for a pulse to bounce from the ocean floor

Answer 1

To create a sonar map of the ocean floor, the relevant data used is the time it takes for a pulse to bounce from the ocean floor.

In sonar mapping (specifically using techniques like sonar and echo sounding), sound pulses are emitted from a vessel or underwater vehicle, and the time taken for these sound waves to travel to the ocean floor and back is measured. This time is then converted into distance using the speed of sound in water, allowing for the mapping of the ocean floor's topography.