Answer to Question 1
Answer: Headings contribute to the document's organization by showing the reader at a glance how the document is organized. They act as labels to group related paragraphs and organize material into short sections. Headings also control the reader's attention, making the text easier to read and helping the audience find the parts they need to reador skip. Finally, headings help readers make connections between subordinate ideas and main ones.
Answer to Question 2
Answer: Lists can show the sequence of your ideas, heighten their impact visually, and help readers find your key points. They also provide readers with clues, simplify complex subjects, highlight the main point, break up the page visually, ease the skimming process, and give readers a breather.