Adderall is a proprietary combination of amphetamine salts that is used to treat ADHD Attention Deficit Hyperactivity Disorder The patient takes one pill before 8am and the drug has completely entered the bloodstream by 8am At 8am the blood concentration of the drug is 33 8 ng ml Adderall has first order elimination kinetics 8 with 7 7 of the drug being removed from the blood each hour I a The concentration of the drug in the patient s blood t hours after 8am is measured to be Ct Write a recursive relation of C 1 in terms of Ct Assume that the patience takes no other Adderall pills What happens in the long run to the amount of Adderall in the system b Solve your recurrence equation to derive an explicit formula for Ct as a function of t When does the concentration of drug first drop below 0 1 ng ml