Input (grade 10): Copland's Music for the Theatre (1925) and the Piano Concerto (1926) were both composed for Koussevitzky.
Output (grade 10): Koussevitzky led the orchestra for the first performance of Copland's early work, "Music for the Theater", in 1925. Koussevitzky also conducted Copland's "Concerto for Piano and Orchestra" in 1927.