Final answer:
The scores for round 1 and round 4 are not provided, so the difference in points cannot be calculated.
Step-by-step explanation:
To calculate the difference in points between the scores after round 1 and after round 4, we need the scores for both rounds.
Unfortunately, the given information does not provide the scores for round 1 and round 4. Without this information, it is not possible to determine the difference in points.