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The isotope radium-226 decays into radon-222, with a half-life of around 1,600 years. If a rock contained 6 grams of radium-226 when it reached its closure temperature but only 0.375 grams when it was discovered, which two statements about the rock are true?
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The isotope radium-226 decays into radon-222, with a half-life of around 1,600 years. If a rock contained 6 grams of radium-226 when it reached its closure temperature but only 0.375 grams when it was