A) How much time is required before a 2. 50-mg sample of 14661Pm(t1/2 = 2020 days) is reduced to 1. 25 mg?
b) An isotope of krypton has a half-life of 3 minutes. A sample of this isotope produces 1000 counts per minute in a Geiger counter. Determine the number of counts per minute produced after 15 minutes
