Please post explanations as well.

12. A medical researcher establishes that a patient's reaction time, r, in minutes, to a dose of a particular drug is r(d) = -0.7d' + d', where d is the amount of the drug, in millilitres, that is absorbed into the patient's blood. a) What type of function is r(d)? b) Without calculating the finite differences, state which finite differences are constant for this function. How do you know? What is the value of the constant differences? c) Describe the end behaviour of this function if no restrictions are considered. 47 d) State the restrictions for this situation