MiniTeaMini

I don't know a jimin

MiniTeaMini

I only know a kitty named Jimim
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MiniTeaMini

HELP! 
          Today's class we tackled about Carbon Dating, I came across a problem that I can't answer to save a life XD
          
          So here's the problem:
          
          If a rock was determined to be around 3.9 billion years old how much Potassium 40 would be left in that rock sample? (Percentage of Potassium 40)
          
          I am confusion and I really need help