Margaret Cho and Carol Burnett describe the cast’s famous unscripted fits of laughter. Harvey Korman’s crack-ups were usually in response to Tim Conway’s facial expressions and nuances of comic delivery. According to Burnett, the cast of “The Carol Burnett Show” would make bets in the green room on how many minutes — or seconds — it would take before Korman cracked up during a scene. Learn more behind-the-scenes stories about Carol Burnett and “The Carol Burnett Show” collaborators on Pioneers of Television: Funny Ladies.