The Brainliest Answer!
When anyone breath in,or inhale,your diaphragm contracts (tightens) contracts and move downward.Thus enable to have space for air or space in your chest cavity,pressure of the air insideĀ is equal to outside so when the spaces the diaphragm creates the air occupies,but when the diaphragm relaxes the air without any space leaves out,usually diaphragm is not only the one who works for successful breathing but those Intercostal muscle men.
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