Recall from Exercise 73, Section 1.1, that the speed of blood located r centimeters from the central axis of an artery is given by the function S(r) = C(R² −  r²), where C is a constant and R is the radius of the artery. What is the domain of this function? Sketch the graph of S(r).

Data from Exercises 73.

Biologists have found that the speed of blood in an artery is a function of the distance of the blood from the artery’s central axis. According to Poiseuille’s law,* the speed (in centimeters per second) of blood that is r centimeters from the central axis of an artery is given by the function S(r) = C(R² − r²), where C is a constant and R is the radius of the artery. Suppose that for a certain artery, C = 1.76 ×10⁵ and R = 1.2 ×10⁻² centimeters.