Valium metabolism The drug Valium is eliminated from the bloodstream with a half-life of 36 hr. Suppose a patient receives an initial dose of 20 mg of Valium at midnight. How much Valium is in the patient's blood at noon the next day? When will the Valium concentration reach 10% of its initial level?

Calculus I

May I please have an explanation of the half-life conditions, pertaining to Biomedical concentration drug dosage? If decaying at half-life, how do I find the half-life for a time Q to reduce to half? How do I determine when a concentration will reach a certain percent of its initial level with a half-life of a certain amount of hours?