A piece of wood from a recently cut tree shows 20 decays per minute. A wooden piece of same size placed in a museum (obtained from a tree cut many…

A piece of wood from a recently cut tree shows $\displaystyle 20$ decays per minute. A wooden piece of same size placed in a museum (obtained from a tree cut many years back) shows $\displaystyle 2$ decays per minute. If half life of $\displaystyle \mathrm{C}^{14}$ is $\displaystyle 5730$ years, then age of the wooden piece placed in the museum is approximately :