Carbon Cycling: Summative This model shows where the carbon was prior to industrialization in the U.S. - 1750. Current measurements show atmospheric carbon concentrations at 860 GtC. The flux causing this increase is not shown. Add an arrow showing the flux that has caused this increase. Make sure to label the flux with the name of the actions causing the flow of carbon and calculate the additional mass of carbon introduced to the atmosphere since 1750.

please help!!
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