OK....I had taxed my brain abt working and non working side when I was cramming for part 1.This is how I ultimately figured it out..and it's stuck with me forever now.....
First clue would be to see the direction of the arrow given
A straight arrow=working side
a slant in the arrow=non working side.
My way of doin it was:
first identify the quadrant indicated by the diagram given.Then imagine this in your mouth.ALWAYS REMEMBER THAT THE ARROW INDICATES MOVT OF THE MANDIBLE.now move your mandible in the direction given by the arrow over the maxillary cusps shown.....you'll figure out which is working and non working side depending on MANDIBULAR MOVT!!
I hope you've understood.Somehow it's clear in my head

Practice a few times....you'll know it in your sleep.good luck!!
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