How do humans impact the carbon cycle?

yes

Explanation:

Human activities have a tremendous impact on the carbon cycle. Burning fossil fuels, changing land use, and using limestone to make concrete all transfer significant quantities of carbon into the atmosphere. ... This extra carbon dioxide is lowering the ocean's pH, through a process called ocean acidification. Humans create horrible pollution, making climate change.

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask