united_states | ethnicgroup | african_americans <tsp> united_states | leadername | barack_obama <tsp> a_wizard_of_mars | country | united_states <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 
barack obama. president of the us is an african american man. which is one of the ethnic groups of the united states. a wizard of mars was published in the united states.the united states is the world's third-largest country by both land and total area