Answer:
(d) There are infinite solutions because there is always another number between any two numbers
Explanation:
The inequality 8 < n < 10 graphs as an open interval on the number line. Its graph is a line segment between 8 and 10, but not including those values.
Any line segment consists of an infinite number of points, and any two points on that segment will have an infinite number of points between them.
The inequality has an infinite number of solutions.
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Additional comment
The number of solutions will be finite if the solution set is restricted to specific values. For example, there is one integer in the solution range.