A, because it the constant variable
Answer:
the first wave of extinction may be related to rapid cooling at the end of the Ordovician Period, and the second phase is widely regarded as having been caused by the sea-level fall associated with the glaciation.
Answer:
You are saying which one but what is which one???
Explanation:
The phosphorus cycle does not include an atmospheric component because phosphorus does not cycle through the atmosphere. In comparison, important processes of the carbon and nitrogen cycle occur in the atmosphere.
