Answer:
It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily. Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges. This contraction creates a vacuum, which pulls air into the lungs.
The ones that are true are: 1,2,3,4
Answer:
I don't know because they want to
Explanation: