Actinium is a highly radioactive element, having a half-life of 21.77 years. Use this information to answer the following questions. In the exponential decay model for Actinium, A(t) = A0e^kt, find the value of k. k = Number (round to 4 decimals). Suppose a scientist in the year 1880 collected 100 grams of Actinium. How much Actinium would remain now (in 2020)? There would be Number grams of Actinium remaining (round to the nearest gram). Suppose a scientist in 1980 wanted to collect and store Actinium, and wanted to be sure to have 70 grams in the year 2020. How much Actinium should she store? She should store Number grams of Actinium (round to the nearest gram).
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The formula for k in an exponential decay model is k = ln(0.5) / -t, where t is the half-life. So, k = ln(0.5) / -21.77 = -0.0318. Show more…
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