Answer:
Option A, oxygen in the atmosphere
Explanation:
The highest level of oxygen reached during this phase of the geological cycle of earth. The oxygen level in Carboniferous period accounted for 35% as compared to 21% of oxygen in the atmosphere in present time.
Due to high oxygen content, the giant and wide varieties of terrestrial animal and plant species evolved. For example – size of insects and carwlies increased, plant became extremely giant, increase in number of tree ferns etc.
Http://www.phschool.com/science/biology_place/biocoach/bioprop/folding.html hope it helpps
I think it’s A. hope this helps
~Hello there! ^_^
Your question: How often is CO2 cycled through the atmosphere?
Your answer: CO2 is cycled through the atmosphere in 350 years.
Hope this helps~
Answer:
A
Explanation:
All systems work together to do-- anything really. Especially to move-