How long (in seconds) would it take a sound to travel underwater across the San Francisco Bay at its widest point of 19 000 meters?

1 answer

Speed of sound in sea water depends on the temperature and salinity.
At 25 degrees and 35 ppt salinity, the speed of sound is approximately 1551 m/s.
So divide 19000/1551 to give the time in seconds it takes.