Yes, most. Not Avatar, but they have a shelf behind you for it. Yes for Everest. Try to keep your pack small, though not much space for them.
Yes, in most of them
Avatar isn't a ride, really. And they have shelf space to hold it while you ride a banchee.
Yes, I brought backpack into all rides. Include at Kali River, careful it could wet. You have also lockers at the entrance
Yes
What about Everest ride
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