Which are true about changes in carbon dioxide in the Earth's atmosphere since 1860? Select the two correct answers. A. The increases in carbon dioxide are caused by human activity.
B. The increases in carbon dioxide can be explained by the Milankovitch cycle.
C. The rate of change in carbon dioxide is exponential.
D. The changes are triggered by a new interglacial period.

Which of the following would most likely be key to gathering evidence that the rna world hypothesis is valid? creation of suitable environments for long-term study of single-celled organisms simulation of early earth conditions and long-term study of the resulting molecules development of a system for studying the microsphere's ability to absorb additional molecules categorization of the different specific conditions that result in the development of microspheres

19. scientists use meteorites that hit earth to provide evidence of the composition of earth's interior because they hypothesize that

Nucleic acid certain protein cell membranes certain carbohydrates