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previous – adj. earlier in time or order
radiocarbon – n. the scientific way of finding the age of something that is very old by measuring the amount of radioactivity in certain forms of carbon in it
author – n. a person who has written something
interact(ing) – v. to talk or do things with other people
cave – n. a large hole that was formed by natural processes in the side of a cliff or hill or under the ground
jewelry – n. decorative objects, such as rings, necklaces, and earrings, that people wear on their body
hypothesis – n. an idea or theory that is not proven but that leads to further study or discussion
disperse(d) – v. to go or move in different directions : to spread apart
