Question: The county that Doris Beck was the first woman to serve as a Mayor of had a population of what in 2010?
Sentence (from "Doris Beck"): Doris Lew Beck (born 1929) is an American Democratic Party politician who was the first woman to serve as Mayor of Livingston, New Jersey, and the first woman to serve as a Mayor in Essex County, New Jersey.
Relevant evidence: Yes