Age of the Earth Vocabulary

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Across
  1. 2. A way to find the age of rocks using radioactive elements
  2. 4. To find an answer using information
  3. 7. Describes an atom that gives off energy as it changes
  4. 9. Information that helps show something is true
Down
  1. 1. The time it takes for half of a radioactive material to decay
  2. 3. To slowly break down or change into something else
  3. 5. A number or answer that is close to the real amount
  4. 6. A pure substance made of only one kind of atom
  5. 8. To look carefully and notice what happens