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December 19, 2014

December 19, 2014

Posted by **Urgent Help** on Thursday, January 10, 2013 at 1:16am.

Show process of how you got this

- chemistry -
**DrBob222**, Thursday, January 10, 2013 at 12:19pmk = 0.693/t

_{1/2}

ln(No/N) = kt

Use No = 100

N = 20

k from above

solve for t in years.

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