Question 319086
{{{r(t) = 2^(-0.002149t)}}}
Find t so that,
{{{2^(-0.002149t)=0.5}}}
{{{-0.002149t=log(2,((0.5)))}}}
{{{t=log(2,((0.5)))/(-0.002149)}}}
{{{t=(log((0.5))/log((2)))*(1/(-0.002149))}}}
{{{t=((-0.301)/(0.301))*(1/(-0.002149))}}}
{{{t=465}}} years