Answer:
Average atomic mass = 6.6575.
Explanation:
As fractions the abundance is 1/4 and 3/4.
The average atomic mass = (5.03 + 3(7.20) / 4
= 6.6575.
The zinc ion +1 can exist but it is very rare and not likely to show up on school work but in your case it did how odd
The answer is B. Lithosphere
Explanation: The upper layer of mantle is a zone of rigid brittle rock. Below the lithosphere is asphalt-like and is called the Asthenosphere.
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