Conversation so far:
What does Kenneth what is the frequency refer to?
Rather was attacked and punched from behind by a man who demanded to know Kenneth, what is the frequency? while a second assailant chased and beat him.
When was Dan Rather attacked?
On October 4, 1986, while walking along Park Avenue to his apartment in Manhattan, Dan Rather was attacked and punched from behind by a man.
What did the attacking man do to Dan Rather?
As the assailant pummeled and kicked Rather, he kept repeating the question.

Question: What did Dan say about the incident?
Self-contained rewrite: What did Dan Rather say about the incident where he was attacked?