Langston Hughes, a prolific writer of the 1920s was concerned with the depicting the experience of urban Black people in the United States.
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Recent studies have shown that air into a house often has higher concentrations of contaminants than heavily polluted air outside.
Among almost seven hundred species of bamboo, some are fully grown at less than a foot high, while other can grow three feet in twenty-four hours.
For make adobe bricks, workers mix sand and clay or mud with water and small quantities of
Membership in labor unions in the United States reached its peak of 17 millions members in