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:
Middle: Self heating containers are really expensive but are useful because they are easy to use, portable, and can be recycled, unlike a camp stove which is not as easily moved.
Explanation:
i neeed a better image for the first an last boo<3
Answer:
they have a fixed pair of magnets and a rolling coil they convert motion into electric energy they are powered by fosile fuels they use reletive motion of a magnet and coil of a wire
Explanation:
An explosion is the only chemical reaction here- it would completely change the substance whereas with the others- every substance has a solid liquid and gas form so they would still be the same substance
