8.) An archaeologist can determine the approximate age of certain ancient specimens by measuring the amount of carbon-14, a radioactive substance, contained in the specimen. The
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formula used to determine the age of a specimen is A = A,2 where A is the amount of
carbon-14 that a specimen contains, A, is the original amount of carbon-14, t is time, in years,
and 5760 is the half-life of carbon-14. A specimen that originally contained 120 milligrams of
carbon-14 now contains 100 milligrams of this substance. What is the age of the specimen, to
the nearest hundred years?