Rewrite the paragraphs in your own words

with pass cost = $25

without pass cost = 3x number of days going the the class

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.

answer; both surfaces of the membrane are nonpermeable

c is the correct answer!