Which of the following collections are sets?
All good players in your school.

Answer

To determine whether the collection "All good players in your school" is a set, we can follow these steps:

### Step 1: Understand the Definition of a Set
A set is defined as a well-defined collection of distinct objects or elements. This means that for a collection to be considered a set, it must have clear criteria for inclusion.

### Step 2: Analyze the Collection
Now, let's analyze the collection "All good players in your school." We need to consider whether there are clear criteria to define who qualifies as a "good player."

### Step 3: Identify the Criteria
In this case, the term "good player" is subjective. Different people may have different opinions on what makes a player "good." For example, some might consider skill level, sportsmanship, or teamwork, while others might have different criteria.

### Step 4: Conclusion
Since there are no universally accepted criteria to define who qualifies as a "good player," the collection "All good players in your school" is not well-defined. Therefore, it does not meet the criteria to be considered a set.

### Final Answer
The collection "All good players in your school" is **not a set**.

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