Consider the concentration C in mg litre of a drug in the blood as a function of the amount of drug injected x in mg and the time since injection t in hours For 0 x 4 mg and t 0 hours we have C f x t 26xte 4 Calculate the following f 3 4 0 00003511 Give a practical interpretation of your answer Choose the best option f 3 4 is A the amount of a 4 mg dose in the blood 3 hours before injection B the change in concentration of a 4 mg dose in the blood 3 hours after injection C the concentration in the blood 4 hours after injection of a 3 mg dose D the half life of a 3 mg dose in the blood 4 hours after injection E the concentration in the blood 3 hours after injection of a 4 mg dose O F the change in concentration of a 3 mg dose in the blood 4 hours after injection