Answer:
You may be referring to the gas that makes up 21% of the earth's atmosphere, which is oxygen.
Explanation:
According to NASA, the gases in Earth's atmosphere include:
Nitrogen — 78 percent
Oxygen — 21 percent
Argon — 0.93 percent
Carbon dioxide — 0.04 percent
(Trace amounts of neon, helium, methane, krypton and hydrogen, as well as water vapor)
Answer:
Electromagnetic Wave Medium Matter:The ability to move or change an object, or what a wave
Longitudinal Wave Trough Rarefaction: The area in a longitudinal wave where the particles are close together.
Transverse Wave Energy Wavelength: The highest point of a transverse wave
Explanation:
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