The circulatory system comprises of the heart, the lungs and the  blood vessels. 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.
Vladimir Putin's Height. 5ft 6.5in (169 cm) The President of Russia. A newspaper once reported that there was criteria for the height of people in official photos with him, and that they shouldn't be taller. Shockingly, the newspaper said with a straight face Vladimir is believed to be between 5ft 2 and 5ft 5.
The tallest U.S. President was Abraham Lincoln at 6 ft 4 in (193 cm), while the shortest was James Madison at 5 ft 4 in (163 cm). The average height of a US president has been 5 ft 10.7 inches and 5 ft 11.6 inches since 1900. Barack Obama, the current President, is 6 ft 1 in (185 cm), and Joe Biden, the current Vice-President, is 6 ft 0 in (183 cm).