To determine the equation that represents the relationship between the number of parts produced \(y\) and the number of hours \(x\), we can observe the values provided:
- When \(x = 0\), \(y = 0\)
- When \(x = 1\), \(y = 125\)
- When \(x = 2\), \(y = 250\)
- When \(x = 3\), \(y = 375\)
- When \(x = 4\), \(y = 500\)
From these values, we notice that for each additional hour, the number of parts produced increases by 125. Therefore, the relationship can be expressed as:
\[ y = 125x \]
Since this equation passes through the origin (0,0), it indicates a proportional relationship between the number of hours and parts produced.
Based on this, the correct response is:
y = 125x, proportional