Need help by people experienced with AppleScript!

open_safari_window("http://www.apple.com")

on open_safari_window(my_url)
	tell application "Safari"
		repeat with i from 1 to 10
			# wake up safari
                        activate
			
			# make a new window
			make new document at end of documents
			
                        # set the URL of this new window
			tell document i
				set URL to my_url
			end tell

                        # sleep 1800 seconds (30 minutes)
			delay 1800
		end repeat
	end tell
end open_safari_window