Answer in true or false:
a, b, d are all variables.

Answer

To determine whether the statement "a, b, d are all variables" is true or false, we can follow these steps:

### Step 1: Understand the terms
- **Variables** are symbols that represent numbers or values that can change.
- **Constants** are symbols that represent fixed values that do not change.

### Step 2: Analyze the statement
- The statement claims that "a, b, d" are all variables.

### Step 3: Identify the nature of a, b, and d
- In mathematics, the letters "a," "b," and "d" can be used as variables, but they can also represent constants depending on the context in which they are used.

### Step 4: Determine the truth value
- If "a," "b," and "d" are being treated as constants in the context of the question, then the statement is false.
- If they are being treated as variables, then the statement would be true.

### Conclusion
- Since the context provided indicates that "a," "b," and "d" are treated as constants, the statement "a, b, d are all variables" is **false**.

### Final Answer
**False**

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