ROCK 'n' Roll turned 50 this morning when an Elvis Presley recording of That's All Right Mama played simultaneously on at least 1200 radio stations worldwide, organisers said. Stations from the UK to Ukraine and Canada to Mexico carried the song as it was fed from Sun Studios, in Memphis, Tennessee. That is where Presley, a 19-year-old truck driver and two other musicians, recorded what many historians call the first rock 'n' roll song. "It was clearly the Big Bang of Rock 'n' Roll," said Kevin Kane, of the Memphis Convention and Visitor's Bureau. Sun Studios is now a national...