The concentration seat of a drug in a patient's blood stream tea hours after injection for the first 24 hours is given by C(t)= 100t/(2t^2 + 75) ng/ml. What is the concentration after one hour? About how many hours will it take for the drug to fall below to nanograms per milliliter in the patient's bloodstream? How long is the drug above 2 ng/mL in the patients bloodstream?