Answer:
1. Authors don't always directly state their purpose in the text because they want readers to use context clues to figure it out and sometimes stating the purpose won't fit with the theme of the text.
2. An author's expertise might affect his or her view by how knowledgeable and passionate they might be about a certain subject. The author might hold bias because of their expertise in the certain subject.
3. An author's language can help convey the perspective on a subject by using different point of views that will get the point across.
4. A reader should pay attention to information that the author chooses to leave out because it's not always going to be apparent in the text. The detail that the author left out that was insinuated could play a big part in the text.
Step-by-step explanation: