Answer:
They developed during the Cambrian time period, which was around 530 million years ago.
Explanation:
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Answer:
They are known as isotopes
Answer:


Explanation:

Solve using the quadratic formula.


Answer:
Answer to the question:
Explanation:
Differences between ionic bond and covalent bond:
The ionic bond occurs between two different atoms (metallic and non-metallic), while the covalent bond occurs between two equal atoms (non-metallic).
In the covalent bond there is an electron compartment, while in the ionic bond there is an electron transfer.
Ionic bonds have a high melting and boiling point, while covalent bonds usually have a low point.