music: 50's Chart Toppers: Name The Artist: I'm Available?

Questions

With which instrument is jazz musician Charlie Mingus principally associated?

In which state would you find the geographical centre of the contiguous United States of America?

Which area of water lies between China and Korea?

In which film did Frank Sinatra win his only Oscar in an acting role?

Who composed the opera buffo The Golden Cockerel in 1909?