Answer:
no one can answer your question because you have shown no arrows.
To supply oxygen to the body, the respiratory system works closely with the circulatory system. As oxygen is taken in into the lungs, it travels through blood vessels, which then circulate oxygen-rich blood to cells and tissues.
Answer:
Around 450 B.C.
Explanation:
The idea was forgotten until the 1800 when John Dalton re-introduced the atom.
sorry I don't know just kidding I know just kidding I don't know
