Which sample contains greater number of nuclei?a 5.00- μCi sample of Pu  240  (half-life 6560y)or a 4.45- μCi sample of Am  243  (half-life 7370y)

The activity -dNdt=λN⇒N=-dNdtT1/2loge2Taking the ratio of this expression for Pu  240 to this same expression for Am  243.NPuNAm=-dNPudtT1/2Pu-dNAmdtT1/2Am=5μCi x 6560y4.45μCi x 7370y=1i.e., the two samples contains equal number of nuclei.