Answer:
1. Afro-American Symphony
2. William Grant Still
Explanation:
William Grant Still, was widely known as Dean of Afro-American Composers, and became popular through his work, titled "Afro-American Symphony", which has the highest number of performance by any Americans until 1950.
Born in 1895, Grant Still, composed about 200 works, which comprises of five symphonies and nine operas.
He is generally know to have written Afro-American Symphony, which has elements of African American music in the work: spirituals, jazz, blues, tenor banjo, work songs, and ragtime.
Hence, the orchestral work that featured spirituals, blues, work songs, ragtime, and jazz as well as a section for tenor banjo, is AFRO-AMERICAN SYMPHONY and WILLIAM GRANT STILL was the composer.
