Across
- 3. Material (solid, liquid, gas) through which sound travels.
- 4. Sound travels fastest through this type of matter.
- 5. Sound that is reflected back to the listener.
- 6. Back and forth movement of an object that produces sound.
Down
- 1. Uses echo sounding to measure the depth of the sea.
- 2. To bounce back (used for sound waves).
- 4. Energy of vibration we can hear.
- 7. Animal that uses echoes to navigate and find food.