this is stumping several people I know , any thoughts ?
12. The amount A (in milligrams) of digoxin, a drug taken by cardiac patients, remaining in the blood t hours after a patient takes a 2 mg dose is given by A = 2(10-.0078t).
(a)How much digoxin remains in the blood of a patient 4 hours after taking a 2 mg dose?
(b)Suppose a patient takes a 2 mg dose at 1:00 p. m. and another 2 mg dose at 5:00 p. m. How much digoxin remains in the patientís blood at 6:00 p. m.?