The exponential growth function is .
The half-life of carbon 14 is years.
Hence, time period is and
Substitue all the values.
\Apply natural logarithm on each side.
\There,the decay constant is .
A piece of charcoal is found to contain of the carbon 14.
When did the tree die from which the charcoal came.
\ and
.
Susbtitute all the values in .
Take natural logarithm on each side.
\ years.
Therefore, the tree die from which the charcoal came in years ago.
The tree die from which the charcoal came in years ago.