The speed S of blood that is r centimeters from the center of an artery S = C(R = r) where C is a constant, Ris the radius of the artery, and S is measured in centimeters per second. After a drug is administered, the artery begins to dilate at a rate . At the constant distance r, find the rate at which S changes with respect to t for C = 1.7 x 105, R = 12 x 10 2 and dt dR = 10 5. dt