Answer:
It's normal
Explanation:
Separators are there to give you enough space, so it's normal if its shifts, for one to two weeks your teeth will move apart slowly until they are far apart enough .. don't mess with it or else the bands will come off.
Blood exchanges carbon dioxide for oxygen in the C.) Alveoli.
If u mean the endocrine system .The endocrine system is the collection of glands of an organism that secrete hormones directly into the circulatory system to be carried towards distant target organs.
