Which composition appears to have had a didactic as well as artistic purpose, with each section emphasizing a different technical aspect of keyboard performance?

It was in ________ in the 1920s that white musicians first formed combos of their own.

A. Cincinnati, Ohio B. Miami, Florida C. Chicago, Illinois D. New Orleans, Louisiana

Short repeated melodic phrases frequently used during the swing era are called ________.

A. riffs B. tags C. breaks D. gigs