Answer:
It plainly establishes that the purpose of the article is to describe the resignation.
Step-by-step explanation:
All texts require the author to describe what his purpose for writing is. In some cases, the purpose of a text can be difficult to establish, as the author does not describe it plainly. However, occasionally, this is easily established. This is the case with this article. By telling us right away that Nixon has resigned, the author allows us to conclude that the purpose of his article is to describe this resignation.