Misc: what date is the beginning of the astrological year?

Questions

Trivia : What is the collective term for a group of nightingales?

Trivia : Who wrote "A Streetcar Named Desire" in 1947?

Trivia : Which director/producer started his career as a student with the film THX-1138 which he later reworked for his feature-directing debut?

Trivia : Which U.S City is the home of the Mowton Record Company?

Trivia : Which martial art has a name that originates from the Japanese word for "gentle"?