For some painkillers, the size of the dose, D, given depends on the weight of the patient, W. Thus, D = f (W), where D is in milligrams and W is in pounds. Interpretations must include full sentences complete with units. (a) Interpret the statement f' (150) = 0.25 in terms of this problem. Include units. (b) Using the info given in a) and if f (150) = 9, estimate f (155). Explain or show supporting work. (c) Interpret the statement f-1(12) = 160 in terms of this problem. Include units. (d) What are the units of (f -1)