you are on a boat in a fog and know there are cliffs ahead of you somewhere, but you cannot see them. You use your fog horn to send out a blast of sound (assume the temperature of the air is 20 oC) and the time it takes for the sound to return to you is 9.2 s. How far away are the cliffs (in metric units)? Hint: Be careful and think about the physics of the problem. You may want to make a sketch of the situation to help you determine the answer.