The half-life of a medication is the amount of time it
takes for the concentration of the drug in the body to
be reduced by one-half. Maddie took a 100-mg dose
of a particular medication and its concentration in
her body was measured every hour. The results are
shown in the table above. If c represents the drug's
concentration in Maddie's body and m represents
the time, in minutes, since she initially took the
medication, then which of the following equations
accurately expresses the drug's half-life?