The ratio of carbon-14 to carbon-12 in a prehistoric wooden artifact is measured to be one-eight of the ratio measured in a fresh sample of wood from the same region. the half life of carbon-14 is 5,715 years. determine its age.

Carbon-14 is radioactive and decays spontaneously. Interaction between stellar radiation and atmospheric nitrogen ensures a constant carbon-14 to carbon-12 ratio in the earth atmosphere. Living plants undergo respiration and take in carbon constantly and maintain a constant carbon-14-to-carbon-12 ratio in their tissues. Carbon atoms in wood artifacts are no longer refreshed such that the relative abundance of carbon-14 decays exponentially.

It takes one half-life for the relative abundance of carbon-14 in a sample to drop by one half. It would thus take three consecutive half-lives for the mass of carbon-14 in the wooden artifact to decrease by a factor of eight.

as seen in the question. Three half-lives would thus correspond to

The age of this sample is therefore at most.

they vary. it used to be meat, grain, bread, candy, beverages, donuts, and fruits/vegetables. now they added exercise in.