Which of the following are statements ?
Earth is a star.

Answer

To determine whether the phrase "Earth is a star" is a statement, we need to analyze what constitutes a statement in mathematical reasoning.

### Step-by-Step Solution:

1. **Definition of a Statement**: A statement in mathematical reasoning is a declarative sentence that is either true or false, but not both.

2. **Evaluating the Phrase**: The phrase "Earth is a star" is a declarative sentence. It makes a claim about the Earth.

3. **Truth Value**: We need to determine the truth value of the claim. In scientific terms, the Earth is classified as a planet, not a star. Therefore, the statement "Earth is a star" is false.

4. **Conclusion**: Since "Earth is a star" is a declarative sentence that can be classified as false, it meets the criteria for being a statement.

### Final Answer:
The phrase "Earth is a star" is a statement because it is a declarative sentence that can be evaluated as either true or false.

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