The domain of a graph refers to the set of possible input values, which in this case corresponds to the number of books that can be purchased at the book fair.
From your description, students can buy up to 10 books, and it appears that the number of books is represented as a discrete set of values. The possible values for the number of books, as you've provided, seem to include: 2, 3, 4, 5, 8, 7, 8, 9, 10, and 11.
However, it seems that 11 exceeds the maximum number of books students can purchase (which is 10), so it should not be included in the domain. Additionally, the value 8 appears twice, but it should only be counted once in the domain.
The complete and correct domain of the graph, considering the constraints given, would be:
Domain: {2, 3, 4, 5, 6, 7, 8, 9, 10}
If your option includes only unique values up to 10, that would be the right choice. If not, please provide additional clarification regarding the options available for selection!