Hello friend
SingleThreadModel is not for exam.
But I think
you should go through singlethread model because
1. If you get any question during exam then you cant argue at that moment.
2. Its better you know what is SingleThreadModel rather than just studying for exam
3. Its not difficult nor time consuming. Its just a concept.
So I suggest you go through that concept so it will help you to solve any question if you encouter in exam plus you know what it is !!
Regards
Rohit