Strontium 90 is a radioactive isotope that decays according to the eqaution A = Age-0.0244t,
where A is the initial amount present and A, is the amount present after t years. If you begin with
350 grams of strontium 90,
(a) How much strontium 90 will be left after 10 years? Round your answer to the nearest tenth of a
gram.
grams
(b) When will 120 grams of strontium 90 be left? Round your answer to the nearest tenth of a year.
years
