Final answer:
Page numbers can be found in various locations such as the bottom left or right footer, or the top left or right header, with top right header being a common placement.
Step-by-step explanation:
Page numbers can be located in various places within a document. The most common placements include:
In the bottom left footer (a).
In the bottom right footer (b).
In the top left header (c).
In the top right header (d).
However, the exact location can vary depending on the formatting preferences of the publication, the style guide being followed, or the instructions given for a particular assignment. In many books, especially those intended for professional or academic use, page numbers are typically found in the top right header (d). This positioning makes it easier for readers to navigate the text, much like the "back" button in a web browser which aids in navigation.
Furthermore, due to the two-side rule that new parts or chapters start on right-side pages, page numbers are often left on the left side (even-numbered pages) to maintain consistency and ease of use.