They should be emailed to you so it's easy to just reprint or have on your phone and they can scan the barcode
Also if you take a picture of the tix they can easily look them up if you lost them.
Sure just reprint the email.
If you ask nicely on the phone, they'll even let you exchange the ticket for a different day. My group last year flaked, leaving me as the only one that actually bought a ticket. My brother in law was going the next week though. I called the ticket line and explained... I didn't want a refund, or even a cheaper ticket, just for a different day... the guy processed the change and even waited for me to get the new ticket via email.
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