Let's say your hand is a bat and the ball is the energy in a sound wave. When the bat sends out a sound wave, it can tell how long it takes to reach and object, bounce off and return. The bat uses this sonar to tell where it is. See if you can use what you learned to help the bat:
A bat is in the middle of a cave. It turns to its left and sends out a squeak of sound energy. The echo returns quickly. It turns back around to the right and sends out another squeak. This one takes longer to return. Which wall is closer to the bat?
____ left
____ right
Name one undersea mammal that uses echoes to find its way:
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