Answer:
Radioactive isotope carbon-14
Step-by-step explanation:
Radiocarbon dating, also known as carbon-14 dating, is a method that is commonly used to determine the age of ancient objects. This method relies on the measurement of the radioactive isotope carbon-14. Carbon-14 is formed in the upper atmosphere by the interaction of cosmic rays with nitrogen-14 atoms. It then enters the food chain and is taken up by plants and animals. Upon death, the carbon-14 in the organism begins to decay, with a half-life of approximately 5,700 years. By measuring the amount of carbon-14 remaining in an ancient object, scientists can determine how long it has been since the object died and calculate its age.
Another method for determining the age of ancient objects is uranium-lead dating, which relies on the measurement of the isotopes uranium-238 and lead-206. This method is useful for determining the age of rocks and minerals, as well as for dating the age of the Earth itself.