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the stable isotope that results from radioactive decay
the time needed for half of a sample of radioactive substance to undergo radioactive decay
an atom that has the same number of protons as other atoms of the same element do but that has a different number of neutron
an atomic nucleus that is undergoing decay
the process by which the age of a rock is determined by measuring the amount of radioactive isotopes present in the rock or rock sample
the process in which a radioactive isotope tends to break down into a stable isotope of the same element or another element
the method used for absolute dating
uses information about rock layers and the fossil record to determine the age relationships between rocks