Q 6.6: The radius of the aorta is about 1cm and the blood flowing through it has a speed of about 30cm/s. Calculate the average speed of the blood in the capillaries, using the fact that although each capillary has a diameter of about 8 x (10)^(-4) cm, there are literally millions of them so that the total cross section is about 2000 (cm)^2.