The answer would be:
Energy
If you'd like to know more about the answer read on:
Amplitude refers to the displacement of a particle from the rest point of a wave. A wave that has high energy, has a high amplitude while one with low energy, has a low amplitude.
You can refer to the image attached to see where the amplitude is on a wave.
The answer to your question is,
Catalysts
-Mabel <3
Answer: 21 percent
Explanation:
According to NASA, the gases in Earth's atmosphere include: Nitrogen — 78 percent. Oxygen — 21 percent. Argon — 0.93 percent.