Conversation so far:
Where was Harburg born?
born Isidore Hochberg on the Lower East Side of New York City.
How did he get the name Yip?
He later adopted the name Edgar Harburg, and came to be best known as Edgar "Yip.
Did Yip attend college?
City College.

Question: What was Harburg's first job?
Self-contained rewrite: What was Yip Harburg's first job?