DNA is the molecule that carries the genetic code. These are found in the nucleus of cells. They copy themselves during replication when a cell divides and splits.
Answer:
I don't know if you can directly prove it with evidence if you haven't observed it but you can maybe take an educated guess by the aftermath of it?
For example, you see a burnt log. At this time, people don't know what fire is. After we study the log, we could see that it takes extreme temperature in order to burn the log and that would help people see that there is a force like fire that can cause this. In a way, finding out that extreme temperatures burns stuff is another step closer to the discovery and proof of fire
I hope that makes sense
Short answer: nitrogen, oxygen, Argon, and
inert gas
The atmosphere contains many gases, most in small amounts, including some pollutants and greenhouse gases.
These contribute to climate change.
Resistance of a material being scratched in known as: Hardness
I think that it is shear adhesion
