That would depend on the current condition of the album. I would suggest talking with someone who deals with old albums and things of that sort. :-)
Practically nothing; they were a popular band back in the day and vinyl copies of their albums will be numerous. Check on eBay what they're selling for, though.
Here's a good site for you to go too: www.prex.com/sell-rock-records.html
I don't know, but I do know that its worth a lot of money.
about £50.00