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Ifa rock had 80 radioactive atoms in it when it was formed and it now has 20 radioactive elements in it, how old is the rock?

2 Answers

6 votes

Answer:

100, it is 100 years old

Step-by-step explanation:

User Rafael Carvalho
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6.0k points
9 votes

Answer:

10 million years

Step-by-step explanation:

User John Smithers
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