A particular bat emits a 25000-Hz ultrasonic sound to navigate in a cave in which the speed of sound is 343 m/s.

- Determine the distance between compressions of the sound signal.

- As the bat hovers 3.5 m from the wall of the cave, calculate the amount of time it takes the sound to travel to the wall and back again.

- As the bat flies toward another bat, explain the frequency that the second bat detects.