Respuesta :
Answer- Parallel.
In-Line Answer:-
In a longitudinal wave, "Energy and the wave are moving in parallel direction"
Longitudinal waves describe the relationship of an energy flow and wave moving i.e. when they move in same direction are always parallel
What is longitudinal waves?
Waves moving in the same direction of the vibration, are called Longitudinal waves. It describes the relationship between the matter movement and the energy flow.
So it can be said that energy and the wave are moving in the same direction are parallel to each other.
Therefore, it's appropriates to say they energy and wave move in the same direction in a longitudinal wave are parallel to each other.
Learn more about longitudinal waves here:
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