Find, which of the following sets are singleton sets :
The set of points of intersection of two non-parallel straight lines on the same plane.

Answer

To determine whether the set of points of intersection of two non-parallel straight lines on the same plane is a singleton set, we can follow these steps:

### Step-by-Step Solution:

1. **Definition of Singleton Set**:
A singleton set is defined as a set that contains exactly one element.

2. **Understanding Non-Parallel Lines**:
Non-parallel straight lines are lines that intersect at one point. This means that they are not parallel and will eventually meet at some point in the plane.

3. **Visualizing the Intersection**:
When we draw two non-parallel lines, they will cross each other at a single point. For example, if we have Line A and Line B, they will intersect at one specific point, which we can call Point P.

4. **Conclusion on the Intersection**:
Since there is only one point of intersection (Point P) between the two non-parallel lines, we can conclude that the set of points of intersection contains only this one point.

5. **Final Statement**:
Therefore, the set of points of intersection of two non-parallel straight lines on the same plane is a singleton set because it contains exactly one element.

### Final Answer:
The set of points of intersection of two non-parallel straight lines on the same plane is a singleton set.

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