Compressions are regions of high pressure due to particles being close together
rarefactions are regions of low pressure due to particles being spread further apart
Longitudinal waves are often demonstrated by pushing and pulling a stretched slinky spring
It is energy associated with gravity or gravitational force. (Potential<span> </span>energy<span> held by an object because of its high position compared to a lower position).</span>
The answer is Electron
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