Question: What a U.S. census-designated place and an unincorporated area in Montgomery County, Maryland who's residence generally identify as living in the most affluent town in all the United States based on median household income ?
Sentence (from "Potomac, Maryland"): Bloomberg Businessweek labeled Potomac as the twenty-ninth richest zip code in the United States in 2011, stating that it had the largest population of any U.S. town with a median income of more than $240,000.
Relevant evidence: No