Let me know if you know the answers from 14 to 20

The large increase in atmospheric carbon dioxide in the last 50 years most likely comes from a. an increase in cellular respiration b. increased decomposition by bacteria c. an increase in the burning of fossil fuels d. an increase in photosynthesis

Which best describes a gene? a. a sister chromatid b. a chromosome c. a tetrad d. a piece of a chromosome

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes