He diagram shows how blood circulates. The bar chart shows the amount of oxygen in blood at ositions A-D, but they are in the wrong order.
a. Which vessels did the blood sample X and Y come from? (mention the letters from diagram I)
b. Name the parts labelled as A, C, and E.
c. What happens if the artery supplying oxygenated blood to the brain is blocked?​

Which statement about relative potential energy of electrons is correct? a. an electron in the 2 p orbital of the second electron shell has more potential energy than an electron in the 2 s orbital of the second electron shell. b. an electron in the 2 p orbital of the second electron shell has more potential energy than an electron in the 3 p orbital of the third electron shell. c. an electron in the 3 p orbital of the third electron shell has more potential energy than an electron in the 2 p orbital of the second electron shell.