A person is given an injection of 300 milligrams of penicillin at time \(t=0 .\)
Let \(f(t)\) be the amount (in milligrams) of penicillin present in the person's
bloodstream \(t\) hours after the injection. Then, the amount of penicillin
decays exponentially, and a typical formula is \(f(t)=300 e^{-0.6 t}\)
(a) Give the differential equation satisfied by \(f(t)\)
(b) How much will remain at time \(t=5\) hours?
(c) What is the biological half-life of the penicillin (that is, the time
required for half of a given amount to decompose) in this case?