Read this: Under the supervision of May and Taylor, numerous restoration projects have been under way involving Queen's lengthy audio and video catalogue. DVD releases of their 1986 Wembley concert (titled Live at Wembley Stadium), 1982 Milton Keynes concert (Queen on Fire – Live at the Bowl), and two Greatest Video Hits (Volumes 1 and 2, spanning the 1970s and 1980s) have seen the band's music remixed into 5.1 and DTS surround sound. So far, only two of the band's albums, A Night at the Opera and The Game, have been fully remixed into high-resolution multichannel surround on DVD-Audio. A Night at the Opera was re-released with some revised 5.1 mixes and accompanying videos in 2005 for the 30th anniversary of the album's original release (CD+DVD-Video set). In 2007, a Blu-ray edition of Queen's previously released concerts, Queen Rock Montreal & Live Aid, was released, marking their first project in 1080p HD.

When was Queen's A Night at the Opera re-released?
What is the answer? (If it cannot be answered, return "unanswerable")
2005