The rides will indicate single rider. Pandemonium, Joker, and Superman are the ones off the top of my head that have single rider and flash pass entry as the same.
Yes, it's a way for them to fill cars that would otherwise travel with empty seats allowing the line to go faster. I don't think all rides allow the single riders to use the flash pass lines so make sure to check the signage for each ride. I know for sure that the "Pandemonium" combines the flash pass and single riders.
yes
From my understanding yes.
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