At time t hours after taking the cough suppressant hydrocodone bitartrate, the amount, A, in mg, remaining in the body is given by A = 10(0.82)(adsbygoogle = window.adsbygoogle || []).push({}); ^{t}.

(a) What was the intial amount taken?

10 mg

(b) What percent of the drug leaves the body each hour?

18%

(c) How much of the drug is left in the body 6 hours after the dose is administered?

A = 10(0.82)^{6}

A = 3.04 mg

(d) How long is it until only 1 mg of the drug remains in the body?

1 = 10(0.82)^{t}

1/10 = 0.82^{t}

ln (1/10) = t ln0.82

t = ln (1/10) / ln0.82

t = 11.6028 hours

Are these correct?

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