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 ofcarbon-14in the organism remains the same. When it dies, it no longer absorbscarbon-14from the air, and thecarbon-14in the organism decays.

The half-life of carbon-14 is 5770 years. Assume an organic sample is11,000years old.

How many half-lives is11,000years? (Round your answer to two decimal places.)