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\textbf{Math 220 (section AD?) \hfill Quiz 6 \hfill Fall 2018} \\
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\textbf{Name}\ \rule{4in}{0.4pt} \hfill
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$\bullet$ You have 20 minutes \hfill $\bullet$ No calculators \hfill $\bullet$ Show sufficient work
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\item (3 points) Suppose that $A$ represents the number of grams of a radioactive substance at time $t$ seconds. Given that $\D{\frac{dA}{dt} = -0.2A}$, how long does it take $20$ grams of this substance to be reduced to $4$ grams?
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\item (4 points) The height of a remote-controlled drone in feet above ground for $t \geq 0 $ seconds is given by the following function.
$$h(t) = \frac{t^{10}}{3e^{2t}}$$
What is the maximum height obtained by the drone?
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\item (3 points) A street light is mounted at the top of a $630$ $cm$ pole. As a woman walks away from the pole, the tip of her shadow is moving $40\%$ faster than she is moving. What is the woman's height?
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