Difference between impressionism and expressionism in music

Why does atlas beg perseus to show him medusas head

To make an etching the artist first coats the entire printing plate with an acid-resistant substance called a made from beeswax, asphalt, and other material. the artist then draws on the coated plate with an etching needle exposing the metal. next the plate is dipped in the plate is removed, the waxy coating removed, and the plate is cleaned, inked and printed.

Choose the term below that you would not find as a musical part of the medieval mass.