Answer: 2 covalent bonds
Explanation:
In H2O molecule, two water molecules are bonded by a Hydrogen bond but the bond between two H - O bonds within a water molecule are covalent. The dotted lines represent a hydrogen bond and the solid lines represent a covalent bond.
Fossils should be your answer
Fossils usually are bones, as bones are strong, and can last for long amounts of time without breaking down.
hope this helps
Https://www.amnh.org/exhibitions/permanent/planet-earth/why-is-the-earth-habitable/life-that-lives-off-the-earth-s-energy/life-at-the-hydrothermal-vents
Hope this helps!
The first cells were identified in a cork bark.
