Answer:
Throughout the late 1940's and 1950's, MGM became the king of the movie musical. And this was largely due to the "Freed Unit." Freed's productions became so popular that the studio could afford to have a SECOND unit for musicals under the direction of Joe Pasternak.
Double variations appear during the Second movement of the Beethoven's Fifth Symphony.
Strip lights Compartmentalized floodlights set up so as to
allow color mixing Low voltage and strip lights are commonly used as light
curtains and for color washes. It is also Known in the UK as a batten. It is
usually seen at the behind the actors backstage.