Question: Which American weekly business magazine labeled Potomac () as twenty-ninth richest zip code in the United States in 2011?
Context: 10048 was the ZIP code assigned to the original World Trade Center complex in New York City.  It was discontinued following the September 11 attacks in 2001.  Years afterward, mail continues to be sent to 10048 by senders who have not updated their mailing lists.  The ZIP code is being kept active by the United States Postal Service (USPS).  It has not been assigned to 1 World Trade Center and other buildings planned for the World Trade Center site, which use the ZIP code 10007 instead. Potomac (   ) is a census-designated place (CDP) in Montgomery County, Maryland, United States, named for the nearby Potomac River.  In 2013, CNNMoney.com listed Potomac as the most affluent town in all the United States based on median household income.  Potomac is also the seventh most top-educated American small town according to "Forbes."  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.  In 2012, The Higley Elite 100 published a list of highest-income neighborhoods by mean household income, which included four neighborhoods in Potomac; one of these neighborhoods, "Carderock-The Palisades" was ranked the highest-income neighborhood in the United States, followed by "Beverly Hills-North of Sunset" in Beverly Hills, CA, and "Swinks Mill-Dominion Reserve" of McLean, VA.  More recently, two Potomac neighborhoods were ranked among the ten wealthiest neighborhoods in the country by CNBC in 2014.  Many Potomac residents work in nearby Washington, D.C. Monocacy Station is an unincorporated community in Amity Township in Berks County, Pennsylvania, United States.  Monocacy Station is located along North Main Street to the north of the Schuylkill River and east of Birdsboro.  Monocacy Station previously had a post office with a ZIP code of 19542; however, this ZIP code was retired in 2016 and the community is now served by the Douglassville ZIP code of 19518. In the Philippines, the Philippine ZIP code is used by the Philippine Postal Corporation (Philpost) to simplify the distribution of mail.  While in function it is similar to the ZIP code used in the United States, its form and its usage is quite different.  The use of ZIP codes in the Philippines is not mandatory, however it is highly recommended by Philpost that they be used.  Also, unlike American ZIP codes, the Philippine code is a four-digit number representing two things: in Metro Manila, a barangay within a city or city district (as in the case for Manila), and outside Metro Manila, a town or city.  Usually, more than one code is issued for areas within Metro Manila, and provincial areas are issued one code for every town and city, with some rare exceptions such as Dasmariñas, which has three ZIP codes (4114, 4115, and 4126) and Los Baños, which has two ZIP codes (4030 and 4031 for the University of the Philippines Los Baños). Whiskeytown is an unincorporated community in Shasta County, California, United States.  The ZIP Code is 96095.  The community is inside area code 530.  Although once a bustling mining town, there are very few people living in Whiskeytown as of today.  The entire town of Whiskeytown was flooded to make way for Whiskeytown Lake in 1962.  The ZIP Code of 96095 is now defunct as it has been taken over by ZIP Code 96033 in nearby French Gulch.  The town of Whiskeytown is now properly part of French Gulch as the original post office and store (that were moved to higher ground in 1962) closed after 40 years.  But Whiskeytown appears on many maps.  All that remains is the relocated store, a few residences, mostly occupied by National Recreation Area personnel, and old mines that are above the water level of the lake.  Whiskeytown is registered as a California Historical Landmark. This is a list of ZIP code prefixes.  Each cell in this table contains a three-digit ZIP code prefix, the state where that ZIP code prefix is located, and the name of the United States Postal Service (USPS) Sectional Center Facility (SCF) that serves that ZIP code prefix, which may be in a different state.  Each SCF may serve more than one three-digit ZIP code prefix.  Each SCF serves local addresses whose five-digit ZIP codes start with the same set of prefixes. ZIP Codes are a system of postal codes used by the United States Postal Service since 1963.  The term "ZIP", an acronym for "Zone Improvement Plan", was chosen to suggest that the mail travels more efficiently, and therefore more quickly (zipping along), when senders use the code in the postal address.  The basic format consists of five digits.  An extended 'ZIP+4' code, introduced in 1983, includes the five digits of the ZIP Code, a hyphen, and four additional digits that determine a more specific location within a given ZIP Code. Bloomberg Businessweek is an American weekly business magazine published by Bloomberg L.P. "Businessweek" was founded in 1929, the magazine was created to provide information and interpretation about what was happening in the business world.  It is headquartered in New York City.  Megan Murphy was appointed editor of the magazine in November 2016. Garnet Valley is an unincorporated community in Delaware County, Pennsylvania, United States.  The name was created by the United States Postal Service in late 2006 to allow residents of Bethel Township and Concord Township who were within the 19061 zip code and were part of the Garnet Valley School District to distinguish themselves from residents of Upper Chichester Township.  The default "city name" for the 19061 zip code is Marcus Hook; other acceptable names in the zip code include Trainer, Linwood, and Boothwyn.  The residents of Bethel Township and Concord Township sought a new postal identity because the zip code "city names" are often confused with actual municipal names. Gladwyne is a very affluent suburban community in Montgomery County, Pennsylvania, United States along the historic Philadelphia Main Line.  In 2011, Gladwyne was ranked the 7th richest ZIP code in the country in a study by Bloomberg BusinessWeek.  The population was 4,050 at the 2000 census.  As Gladwyne is neither an incorporated area nor a census-designated place, all data are for the ZIP code 19035, with which the community is coterminous.
Answer: Bloomberg Businessweek