Concept explainers
Chemistry A chemist has a 100-gram sample of a radioactive material. He records the amount of radioactive material every week for 7 weeks and obtains the following data:
(a) Using a graphing utility, draw a
(b) Using a graphing utility, build an exponential model from the data.
(c) Express the function found in part (b) in the form .
(d) Graph the exponential function found in part (b) or (c) on the scatter diagram.
(e) From the result found in part (b), determine the half-life of the radioactive material.
(f) How much radioactive material will be left after 50 weeks?
(g) When will there be 20 grams of radioactive material?
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Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (4th Edition)
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