Question 1030965
 A scientist has 68 grams of a radioactive substance that decays at an exponential rate. Assuming k = -0.4, how many grams of radioactive substance remain after 10 days.
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A(t) = P*e^(-0.4t)
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A(10) = 68*e^(-4) = 1.25 grams
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Cheers,
Stan H.
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