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Elena-2011 [213]
3 years ago
15

A radioactive element has a half-life of 1000 years. A rock contains 6.25% radioactive material. How old is the rock?

Biology
1 answer:
Natali5045456 [20]3 years ago
7 0

ANSWER:

Radioactive element life years = 1000/2 = 500yrs.

So, Rock years

  • 6.25/100 × 500
  • 31.25years.
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