An equation can be broken down into expressions, terms, variables, constants, and coefficients.

In the equation \(0.4 - 7x = 3\), the constants are the numerical values that do not contain variables.

Here, \(0.4\) and \(3\) are constants. The term \(-7x\) includes a variable (\(x\)), so it's not a constant.

Therefore, the correct response is **0.4 and 3**.