Concept explainers
Radioactive Decay Strontium-90 is a radioactive material that decays according to the function , where is the initial amount present and is the amount present at time (in years). Assume that a scientist has a sample of 500 grams of strontium-90.
(a) What is the decay rate of strontium-90?
(b) Graph the function using a graphing utility.
(c) How much strontium-90 is left after 10 years?
(d) When will 400 grams of strontium-90 be left?
(e) What is the half-life of strontium-90?
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Precalculus
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