Deidara effortlessly wins the latter two, and also defeats the first scenario, despite the incredibly haxxed, non-existent form of Tenten.
While the Fan has been hyped to be quite useful, we have no idea how it works or which kind of elemental attacks it grants its user, not to mention that it's close to being completely featless. We have no idea what kind of attacks it grants the user, are they simple elemental blasts, like Kakuzu uses, or are they perhaps something else? Are they fast or slow? Does it take a lot of time to prepare for them? Are they spammable? The unanswered questions are simply too many. Due to this lack of feats, and of course, the fact that Tenten has no experience using the fan whatsoever, no one here can say for sure that she can take on someone of Deidara's caliber. So, as of now, I'll stick with Deidara on all scenarios, although the first one would without be a lot tougher than the other two.