Which of the following statements are true ?
`phi sub {a,b,c} `

Answer

To determine whether the statement "φ is a subset of {a, b, c}" is true, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terminology**:
- The symbol "φ" represents the null set or empty set, which contains no elements.
- A subset is a set where every element of the subset is also an element of the larger set.

2. **Identify the Larger Set**:
- In this case, the larger set is {a, b, c}. This set contains three elements: a, b, and c.

3. **Evaluate the Null Set**:
- The null set φ has no elements. Therefore, there are no elements in φ that could possibly not be in {a, b, c}.

4. **Check the Definition of Subset**:
- For φ to be a subset of {a, b, c}, every element of φ (which is none) must be in {a, b, c}. Since there are no elements in φ, this condition is trivially satisfied.

5. **Conclusion**:
- Since the null set is a subset of every set, we can conclude that the statement "φ is a subset of {a, b, c}" is true.

### Final Answer:
The statement "φ is a subset of {a, b, c}" is true.

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