Drug Diffusion in the Bloodstream After a drug is taken orally, the amount of the drug in...

Drug Diffusion in the Bloodstream After a drug is taken orally, the amount of the drug in the bloodstream after t hours is f(t) units. Figure 1 shows partial graphs of f′(t) and f″(t).

Figure 1

(a) Is the amount of the drug in the bloodstream increasing or decreasing at t = 5 hours?

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(b) Is the graph of f(t) concave up or concave down at t = 5 hours?

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(c) When is the level of the drug in the bloodstream decreasing the fastest?

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(d) At what time is the greatest level of drug in the bloodstream reached?

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(e) When is the level of the drug in the bloodstream decreasing at the rate of 3 units per hour?