About Question enthuware.ocpjp.v7.2.1396 :

[admin]

Well, if there is no preemptive scheduling, how will the other thread get to run before the main thread is complete?

[kwetal]

Any call from the user program to a system or kernel routine gives the system the opportunity to intercept the current thread and yield to another thread.

[admin]

And I will be repeating what I said earlier in this thread. This argument is really a stretch and I do not think it is relevant for the purpose of the exam.
Here is an interesting discussion that I found: https://stackoverflow.com/questions/145 ... preemptive

HTH,
Paul.