Physics

Problem

The half-life of a certain radioisotope is

1.0\,\text{year}

. Its decay constant expressed in

\text{s}^{-1}

is closest to a)

6.9\times10^{-9}

4.6\times10^{-8}

2.2\times10^{-8}

3.2\times10^{-8}