Short answers, pulled from the story.
Rock 'n' Roll Music was released on the 7th of June 1976 in the United States on Capitol Records (catalogue number SKBO 11537) and on the 11th of June 1976 in the United Kingdom on Parlophone (PCSP 719).
Rock 'n' Roll Music reached number 2 on the Billboard 200. It was kept off the top position by Paul McCartney's Wings at the Speed of Sound.
Lennon wrote an angry letter to Capitol Records saying the cover "looks like a Monkees reject". He suggested using photographs by Astrid Kirchherr or Jurgen Vollmer, who had photographed the Beatles during their Hamburg days, and even offered to design the cover himself but was declined.
George Martin, described as "appalled" by the original tapes Capitol planned to use, reworked the already mixed recordings by reversing the left and right channels and slightly narrowing the stereo on seven tracks, including "Twist and Shout", "Roll Over Beethoven", and "I'm Down". EMI refused to use Martin's modified tapes for the UK release.
Capitol originally planned "Helter Skelter" as the A-side, but when a made-for-television film about the 1969 Charles Manson murders was announced for April 1976, Capitol reversed the sides. "Got to Get You into My Life" became the A-side and reached number 7 on the Billboard Hot 100.
Rock 'n' Roll Music is a 28-track double album. It includes 15 Lennon-McCartney songs, one George Harrison composition ("Taxman"), and a dozen cover versions of songs by rock and roll composers such as Chuck Berry, Little Richard, Carl Perkins, and Larry Williams. It was also the first Beatles album to include "I'm Down" on an album release outside of Spain.