In the fifth paragraph, the author mentions that she "got up at two or three in the morning and wrote" primarily to

The author presents this information to show how she was dedicated to writing at a great intensity and how it was a very influential activity in her life.

You have not shown the text your question refers to. This prevents me from giving you a specific answer, but I will try to help you in the best possible way.

From the context of your question, we can see that you are referring to an autobiography. For this reason, we can state that:

An autobiography is a text where the author presents and explains facts of his/her own life.
When an author shows, in an autobiography, that he got up at dawn to write, that author wanted to show how writing was important to him.

In this case, the author wants the reader to realize that writing was an activity that demanded a lot of dedication and that the author was willing to devote and write with great intensity, even if it required sacrifices.

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https://brainly.com/question/8121767?referrer=searchResults