Questions 1 and 3 are based on this passage

Early in the twentieth century, San Francisco was the main venue for African American jazz musicians on the West Coast of the United States. Musical activity was centered in a district known as the Barbary Coast, where an abundance of nightclubs provided ample work opportunities for local players and drew musicians and other entertainers, many of them African American, from throughout the country. In 1921, as part of its Prohibition-era efforts, the government closed the Barbary Coast. This closure was the decisive event that established Los Angeles as the premier center for jazz on the West Coast. Once the Barbary Coast was shut down, it became far harder for jazz musicians to make a living in San Francisco; thus, many headed south to Los Angeles.
Yet even before that closing, the center of jazz activity had begun to swing southward. With the largest and fastest growing African American urban community in the West, as well as the growing movie industry and an emerging recording industry, Los Angeles was already a magnet for jazz musicians from other parts of the country, especially New Orleans, where jazz players suffered a devastating blow with closing of the Storyville district in 1917.