Question 729995
Let A = amount
let I = initial amount
let t = time in years
General decay eqaution, {{{A=I*e(-kt)}}}


Starting at any I, half life of 1580 years makes {{{(1/2)*I=I*e^(-k*1580)}}},
{{{1/2=e^(-k*1580)}}}
Find k.
...
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