Conversation so far:
who owned the new york yankees before george steinbrenner
Columbia Broadcasting System owned the New York Yankees before George Steinbrenner.
how long did george steinbrenner own the new york yankees
George Steinbrenner was the New York Yankees' principal owner from 1973 until his death in 2010.
who is the new york yankees’ first general manager
The longest tenured general manager for the New York Yankees is Ed Barrow
how long did Ed Barrow serve as general manager for the new york yankees
Ed Barrow served as GM for the New York Yankees for 23 years

Question: what do the general managers of the team do
Self-contained rewrite: what do the general managers of the new york yankees do