Question 1118557
One year of time pass
{{{1*e^(-k*1)=1-0.0354}}}


{{{e^(-k)=0.9646}}}


{{{ln(e^(-k))=ln(0.9646)}}}


{{{-k=-0.03604}}}


{{{k=0.03604}}}

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The model equation: {{{highlight_green(N(t)=N[o]e^(-0.03604t))}}}

FINDING HALF-LIFE

{{{e^(-0.03604t)=0.5/1}}}

{{{e^(-0.03604t)=0.5}}}

{{{ln(e^(-0.03604t))=ln(0.5)}}}

{{{}}}

{{{t=ln(0.5)/(-0.03604)}}}


{{{t=highlight(19.23)}}}  or  about 19 years 3 months