Neutron activation analysis for a sample of a rock revealed the presence of 140 56ba ,which has a half-life of 12.5 days . assuming the isotope was freshly separated from its decay products, what is t

Neutron activation analysis for a sample of a rock revealed the presence of 140 56ba ,which has a half-life of 12.5 days . assuming the isotope was freshly separated from its decay products, what is the mass of 140 56ba in a sample emitting 1.00 mci of radiation?