Final answer:
The student's question involves a logical arrangement with a conditional relationship between swimmers P, T, S, and J. Depending on whether P swims immediately after T, J will swim immediately after S or not.
Step-by-step explanation:
The linear arrangement: Unless P swims immediately after T, J swims immediately after S, suggests a conditional relationship between swimmers' positions.
If we do not have P swimming directly after T, then it must be that J is swimming immediately after S.
To depict this, consider two scenarios. In the first scenario, we place P immediately after T, in which case the positioning of J and S is not constrained by the given condition.
Hence, the arrangement could be T, P, S, J, or T, P, J, S, and so on.
In the second scenario, P does not swim immediately after T.
In this situation, J must swim right after S.
Thus, the possible arrangements could be T, S, J, P, or T, S, J, and others based on the number of swimmers and additional constraints not specified in the prompt.