To piggyback Kristen's answer. Yes, on most trails but not all. At the entry kiosk or the visitor's center they will have trail maps with the routes that mountain bikes are allowed on highlighted.
Yes, but not on all the trails. Ask for a trail map from the ranger, they'll point you in the right direction. Bikes are allowed on all the campground area. Saw lots of kids playing on the roads.
Yes
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