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2. This second activity is to get you familiar with taking a function and finding the IRC, be able to interpret results and understand the graph of the function. The quantity (in mg) of a drug in the blood at time t (in minutes) is given by the function: Q (t) = 25(0.8)t a. Find Q(3) and interpret its meaning with units. b. Estimate the rate of change of the quantity at t - 3, Q'(3) using an error of h = 0.001. Interpret these results and be sure to include appropriate units! c. In Desmos, graph the original function, Q (t) - 25(0.8), and realize you will have to use x for the variable and graph the tangent line (which you will have to find) at the point t = 3