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Chemistry, 28.07.2019 23:10 scottbrandon653
Arock has 50 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 50 percent of its original amount of potassium-40 remaining in it. potassium-40 has a half...
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