Fluid Flow; Bernoulli's Equation

[Proleague]

Homework Statement

Using the data of Example 10-11, calculate the average speed of blood flow in the major arteries of the body, which have a total cross-sectional area of about 2.0cm²

Homework Equations

well... Actually, I don't know how to solve this problem.
The Example 10-11 gives some of datas.

"The blood returns to the heart via the veins. The radius of the aorta is about 1.2cm, and the blood passing through it has a speed of about 40cm/s. A typical capillary has a radius of about 4 x 10^-4cm, and blood flows through it at a speed of about 5 x 10^-4 m/s.

The Attempt at a Solution

I do now know what should I use equation first, so would you explain detail to me to learn how to solve this problem easily. Please answer the questions!

 

[Chestermiller]

All that blood flows through the aorta, and the volumetric flow rate of this blood is the cross sectional area of the aorta times the flow velocity in the aorta: $Q=\pi (1.2)^2(40)=181 cc/sec$. The total cross sectional area of the major arteries are 2 cm^2. So the velocity in these arteries is $v=\frac{Q}{A}=181/2=90.5 cm/sec$

Sounds high.