In the equation \(0.4 - 7x = 3\), the constants are the fixed numerical values that do not contain variables.
Here, the constants are:
- \(0.4\) (the constant on the left side)
- \(3\) (the constant on the right side)
So the constants in the equation are \(0.4\) and \(3\).
Therefore, the correct answer is 0.4 and 3.