You might need to look closely at text features to get a sense of the author's purpose in an informational text.
Below, look at part of the table of contents for a book called The Wealth of Nations,
and see if you can figure out the purpose.
Table of Contents
1.1. Of the Division of Labor
1.2. Of the Principle which gives Occasion to the Division of Labour
1.3. That the Division of Labour is Limited by the extent of the Market
1.4. Of the Origin and Use of Money
1.5. Of the Real and Nominal Price of Commodities, or of their Price in Labour,
and their Price in Money 1