The amount of a sample remaining after t days is given by the equation mc001-1.jpg, where a is the initial amount of the sample and h is the half-life, in days, of the substance. a scientist has a 10-mg sample of a radioactive isotope. the isotope has a half-life of 8 days. after 16 days, how much of the radioactive isotope remains? 2.0 mg 2.5 mg 5.7 mg 7.1 mg