@X@user.full_name@X@ @GMU: Radioactive substances decay by f…
@X@user.full_name@X@ @GMU: Radioactive substances decay by first-order kinetics. How many days would be required for a sample containing phosphorus-32 to decrease to 59.86% of its initial activity? The half-life of phosphorus-32 is 1.42e1 days.