How does the author develop the central idea of the section “The Great Devide”?

i do not know and i have a 100 in this class

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

the most common type of reef is the fringing reef. this type of reef grows seaward directly from the shore. they form borders along the shoreline and surrounding islands.