I think the problem is that not all the students had access to the testbank. If the professor had announced to all students to use the testbank questions to study from, then that's fair for all students. ALso, the students should have asked if using the test questions was cheating, the fact they didn't implies that they knew it was an unfair advantage.
Jewelry? How 1950's of you, next you'll be suggesting that women douche with Lysol: http://contexts.org/socimages/2008/08/21/vintage-zonite-douche-ads/
http://contexts.org/socimages/2008/08/21/vintage-zonite-douche-ads/