Answer:
Apitite
Explanation: Apitite has a hardness of 5 it can scratch flouride but Quartz has a hardness of 7 meaning it can scratch Apitite
C
Brown algae
Im pretty sure this is correct
Idk I’m really sorry my friend
It gives a better foundation for the top part of your vertebrae (that are smaller), as it is bigger, it can support the rest of your vertebrae better.