How does 19th-century orchestral music differ from 18th-century orchestral music?

In what ways is an operetta different from an opera?

a. An operetta uses a more adventurous harmonic language. b. An operetta is an amateur production, not performed for profit. c. An opera uses an orchestra, whereas the operetta is performed unaccompanied. d. An operetta uses spoken dialogue and is typically more light-hearted.

Three innovative jazz trumpeters were Louis Armstrong, Roy Eldridge and

a. Count Basie. b. Coleman Hawkins. c. Dizzy Gillespie. d. Art Tatum.