Which of the following does not represent a mechanical wave?
sound
waves in the ocean
waves in a wheat field
light

The other person who answered is incorrect- the real answer is light.

Explanation:

  A mechanical wave is a wave that requires a medium. A medium is any substance that has a defined set of physical properties and can transmit energy. A medium can be a solid, liquid, or gas. Some examples of a medium include an iron bar, the ground, water, lava, air, and helium in a balloon.

  The answer is not sound because sound travels through waves through the air. If you were to put a source of sound in a container that contains no air, you would not be able to hear the sound through the container. Since sound has a wave and a medium, it is a mechanical wave.

  The answer is not waves in the ocean because, obviously, this is a wave. Its medium is the water. Since it has a wave and a medium, it is a mechanical wave.

  The answer is not waves in a wheat field because, again, this is a wave. The medium is the air. Since it has a wave and a medium, it is a mechanical wave.

  The answer is light. Light travels through electromagnetic waves. However, it does not require a medium. Light can travel not only through air and solid materials, but also through the vacuum of space. Since light does not require a medium, it is not a mechanical wave.

I hope this helps !! :)

i think it's 35 meters