Nearly all vendors take card, they also have an ATM on the North side.
Yes you can
Yes at most vendors you can use a debit card.
I've only ever used card at the farmers market and never run into any place that only takes cash. Only very exceptionally would you HAVE to have cash
Some take cards, though most prefer cash. The ATMs charge a pretty hefty fee, so it's better to get cash before you go.
Most places are set up for major credit cards, so long as your debit card has visa/mc/amex/discover backing, you should be good. If it's strictly an ATM card, you might need to visit one of the ATMs that are in the corners of the park. I'd check with the vendor before purchasing anything.
Depends on the stand. ATMs are available on site.
Thanks! Your answer is awaiting moderation.