You have been asked to prepare an 80.0 mg/mL aqueous oral solution of a drug for a patient. However, after 120 hours (5 days), you notice that the solution has started to discolour. You assay the solution, and find that the drug concentration is now only 72.5 mg/mL. (a) What is the ratio strength of the drug in the formulation? (b) Assuming first order degradation kinetics, estimate the concentration of the drug in the formulation one day after being made and also the t90 (in days) for the drug in the formulation. (c) The activation for the degradation reaction is 126 kJ/mol. Estimate the increase in shelf life (t90) (in days) for the drug in the formulation if it is stored in the refrigerator at a temperature of 5.0 C. In your calculations assume that the rate constant calculated in part (a) of this question was at a temperature of 20.0 C. (d) If the active in this drug formulation degrades mainly via oxidation, list three strategies that may be used to maximise the shelf life of this product.