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Chemistry, 20.01.2020 09:31 jahsehsgold
Arock has 25 percent of its original amount of potassium-40 remaining in it; potassium-40 has a half-life of 1.25 billion years. how long ago was the rock formed? 1.25 billion years ago 2.50 billion years ago 5.00 billion years ago 6.25 billion years ago
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Arock has 25 percent of its original amount of potassium-40 remaining in it; potassium-40 has a hal...
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