please help with this im stuck on it!!

1. [6 marks] Through a medical study, it was determined that the rate of change of the concentration (in mg/cma) of a drug in a patient's bloodstream t min after it is administered is given by: _4et/60 I t = C ( ) 60(et/6o + 1)2 so (a) Evaluate / C" (t) dt to one decimal place and interpret your result. 0 (b) If the initial concentration of the drug is 4 mg/cm3, what is the concentration of the drug one hour after it has been administered? Express your answer to one decimal place