Question 1090059
The formula for this radioactive decay would be .5=1 x e^-60k, where .5 equals the half-life, and k equals the radioactive constant. So:
.5=e^-60k
ln 0.5=ln e^-60k
ln 0.5=-60k
k=0.01155245300933242182362053535764
So:
10=400*e^-0.01155245300933242182362053535764*t
.025=e^-0.01155245300933242182362053535764t
ln 0.025=ln e^-0.01155245300933242182362053535764t
t=319.3157 years
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