The United States of America, commonly referred to as the United States, America, and sometimes the States, is a federal republic consisting of 50 states and a federal district. The 48 contiguous states and Washington, D.C., are in central North America between Canada and Mexico. Wikipedia

Africa is the world's second-largest and second-most-populous continent. At about 30.2 million km² including adjacent islands, it covers six percent of the Earth's total surface area and 20.4 percent of the total land area. Wikipedia