Solve the Problem $\mathrm{A}=\mathrm{Ie}^{\mathrm{kt}}, \mathrm{A}$ Is the Amount of Radioactive Material Remaining from an Initial

Multiple Choice

Solve the problem.
-In the formula $\mathrm{A}=\mathrm{Ie}^{\mathrm{kt}}, \mathrm{A}$ is the amount of radioactive material remaining from an initial amount I at a given time $t$ and $k$ is a negative constant determined by the nature of the material. An artifact is discovered at a certain site. If it has $79 \%$ of the carbon-14 it originally contained, what is the approximate age of the artifact? (carbon-14 decays at the rate of $0.0125 \%$ annually.) (Round to the nearest year.)

A) 6 $320 \mathrm{yr}$
B) $1886 \mathrm{yr}$
C) 1680 yr
D) 819 yr