3. Which of the following statements are accurate?
A. Veins in the pulmonary circuit carry oxygen-rich blood
B. Arteries in the pulmonary circuit deliver oxygen-rich blood to the body tissues.
C. All arteries carry blood away from the heart
D. Arteries in the pulmonary circuit deliver oxygen-poor blood to the lungs.
E. Veins in the systemic circuit return oxygen-poor blood to the heart.

A.) Veins in the pulmonary circuit carry oxygen-rich blood

red blood cells are used to circulate oxygen through out the body, thus it is true.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.