How do Paulsen’s uses of repetition function in the novel to create a particular mood and/or convey ideas?

Why does Paulsen use a third-person omniscient narrator, and how does point of view affect the reader’s understanding of the story? How would the story have been different if Brian or Derek narrated it?

Even though The River feels like it could have actually happened, it is a fictional story. How does Paulsen create this realistic impression? What literary devices and plot elements contribute to the true-to-life depiction of the story?