The main objective of the circulatory system is  transporting oxygenated (rich saturation of oxygen) blood around  the body. The de-oxygenated blood enters through the vena cava and  into the right atrium of the heart. It then goes to the right  ventricle, directly below the atrium.
Pyramid of the Sun. Less than half a mile south of the Pyramid of the Moon is the Pyramid of Sun. At a height of more than 200 feet (63 meters) and a base more than 730 feet (225 meters) long on each side, this pyramid is one of the largest structures created in the pre-Columbian New World. It would have been completed around 200 AD.
Height of a Pyramid. The height of a pyramid can be calculated if the apothem of the side and the base are known. Apply the Pythagorean theorem and calcuate the height of the shaded right triangle: Calculate the apothem and height of a hexagonal pyramid whose base edge is 16 cm and its lateral edge is 28 cm.