(a) The volume flow rate in an artery supplying the brain is 3.6 × 10-6 m3/s. If the radius of the artery is 5.2 mm, determine the average blood speed.
(b) Find the average blood speed at a constriction in the artery if the constriction reduces the radius by a factor of 3. Assume that the volume flow rate is the same as that in part (a).