How might free movement across an internal border within the us be limited? a. a state might limit the types of plants and animals that can enter its borders. b. a state might pass a law limiting the number of citizens from other states that visit each year. c. a state might require a passport to enter its borders. d. a state might pass tariffs on goods that are imported.

The first immigrants to settle in what is now the united states were the ancient ancestors of modern native americans. the precise routes of those first north american immigrants are disputed, but there is no uncertainty about the fact that every human being on the continent is either a recent immigrant or a descendant of earlier immigrants. since the first immigrants came here from asia more than thirteen thousand years ago, there have been four large and easily recognizable modern waves of immigrants into the united states.