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\item<2-> The United States of America \uncover<3->{(USA),}
\item<4-> commonly known as the United States (U.S. or US) or America,
\item<5-> is a country mostly located in central North America, between Canada and Mexico.
\only<6-7>{
\item<6-> It consists of 50 states, a federal district, five major self-governing territories, and various possessions.
\item<7-> At 3.8 million square miles (9.8 million km2), it is the world's third- or fourth-largest country by total area.