Physics

Problem

An isotope used in cancer therapy has a half-life of

12\,\text{h}

. At the start of a treatment its activity is

1.0\,\text{Ci}

(

1\,\text{Ci}=3.7\times10^{10}\,\text{Bq}

). After some time its measured activity is

5.78\times10^{8}\,\text{Bq}

. How many hours have elapsed since the start? a) 60\,h b) 72\,h c) 50\,h d) 48\,h