Question

6.geochemical process that release carbon dioxide

7.store carbon underground
8.human activities that release carbon dioxide

Answer 1

geochemical: I guess when volcanoes erupt?
Store Carbon: when lots and lots of plants die and then get buried or covered up by more organic material and soil, carbon builds up underground.
Human Activities: burning fossil fuels (like burning coal for power plants, driving cars, lighting fires for stoves or farming), breathing