Answer:
I think it's A
Explanation:
I'm sorry if it's not correct. I'm tryna get enough points to ask my question
Answer:
The heart and the blood vessels are a part of the circulatory system. The blood vessels include the arteries, veins and capillaries. The lungs are considered to be the pulmonary part of the circulatory system. The heart is the cardiovascular part of the circulatory system and the vessels are the systemic part of the circulatory system. The main function of the circulatory system is to supply all parts of the body with oxygenated blood and to take away the deoxygenated blood from all parts of the body.
=Spectral lines are produced by transitions of electrons within atoms or ions. As the electrons move closer to or farther from the nucleus of an atom (or of an ion), energy in the form of light (or other radiation) is emitted or absorbed.…