Why does the author switch from narrative writing to a letter?

Read the excerpt from part 3 of the call of the wild. but it was in giving the law and making his mates live up to it, that buck excelled. dave and sol-leks did not mind the change in leadership. it was none of their business. their business was to toil, and toil mightily, in the traces. so long as that were not interfered with, they did not care what happened. billee, the good-natured, could lead for all they cared, so long as he kept order. the rest of the team, however, had grown unruly during the last days of spitz, and their surprise was great now that buck proceeded to lick them into shape. what theme is most supported by the ideas in this excerpt? good leaders are strong and intelligent. loyalty can be a very powerful force. only the strong survive in the wilderness. we are all ruled by our natural instincts.

How does the author use the character of torvald helmer to explore a social use? -by revealing the changes that can happen to a person who has gotten wealthy quickly - by revealing attitudes related to spending and saving that men held during the victorian era -by revealing the bad financial advice that was given to many people in the victorian era -by revealing the hardships that fell on many people who lived during the victorian era

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