Back to the old chestnut of apostrphes indicating missing letters (see the CD's, DVD's debate!). A and D are missing, they need apostrophes...
Nope, sorry. Ampersand is a symbol that represents the word 'and'; it is not an abbreviation.
Again, this is a bad example as most people would favour the 'n'... or was that deliberate to throw people off the scent, I wonder?
Rock 'n' Roll is correct for the music style, but in this case the ampersand simply replaces the full word, AND.
i never noticed it but it is actually rock 'n' roll