Construct a model of the carbon cycle that explains why the carbon dioxide levels are increasing.
NEED HELP ASAP

Carbondioxode is present in the atmosphere which is used by plants during the process of photosynthesis. From this process, plants make their food by using carbondioxode from the air for making glucose. The carbondioxide is released in the atmosphere by the animals during respiration process and the carbon concentration is stable.

Increase occurs in carbondioxide concentration due to human activities such as use of fuels in vehicles and industries.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

weathering is the answer.