Answer:
The oceanic crust is formed by partial melting of the mantle at mid-ocean ridges. The continental crust is formed even more cycles of partial melting over time, resulting less dense rocks.
Explanation:
The mantle, oceanic crust, and continental crust all have different compositions due to a process called partial melting.
This is where you start to melt a rock, but don´t melt it all the way.
When you partially melt a rock, certain chemical elements tend to stay in the solid rock while others tend to go into the melted part.
As a result, the rock that forms from that melt is less dense than the original rock.
If you then partially melt that rock, you get a rock that is even lighter.
it forms covalent bonds by sharing electrons
Answer:
Phylogenetics
Explanation:
An evolutionary tree can also be called a phylogenetic tree, or a just a phylogeny, and phylogenetics is the study of determining evolutionary relationships, or patterns of descent of organisms.
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6)active immunity occurs when the person is exposed to a live pathogen and passive immunity<span> can occur naturally.
7) you can buy bacteria killing soap and keep your house bacteria free. wipe down everything that hands touch everyday.
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