The isotope known as carbon-14 is radioactive and will decay into the stable form nitrogen-14. As long as an organism is alive, it ingests air, and the level of carbon-14 in the organism remains the same. When it dies, it no longer absorbs carbon-14 from the air, and the carbon-14 in the organism decays. The half-life of carbon-14 is 5770 years. Assume an organic sample is 15,000 years old.

Determine how many half-lives are in 15,000 years. Then use this answer to determine what percentage of the original amount of carbon-14 remains after 15,000 years. Round your answer as a percentage to the nearest whole number.
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