6 is the answer to this
hope it helps
The two differences you see when comparing the four chambers of the heart is that the arteries have a thicker wall and veins have thin walls and that the arteries carry oxygenated blood away from the heart which means they get more pressure than veins.
it has an alternating chemical<span> phosphate and </span>sugar<span> backbone, making the 'sides' of the ladder. (Deoxyribose is the name of the </span>sugar<span> found in the backbone of DNA.) In between the two sides of this </span>sugar<span>-phosphate backbone are four nitrogenous bases: adenine (A), thymine (T), </span>cytosine<span> (C), and guanine (G).</span>