united_states | ethnicgroup | african_americans <tsp> united_states | leadertitle | president_of_the_united_states <tsp> 250_delaware_avenue | location | united_states <tsp> united_states | leadername | barack_obama <sep> the united states of america (usa or usa), commonly known as the united states (us or us) or america, is a country primarily located in north america it consists of 50 states, a federal district, five major unincorporated territories, nine minor outlying islands, and 326 indian reservations the united states is the world's third-largest country by both land and total area 
250 delaware avenue is located in the united states where barack obama is the leader and his title is president of the united states. one of the ethnic groups of the united states are the african americans.the united states is the world's third-largest country by both land and total area