Misc: Which member of the UK government resigned after a scandal in 1983?

Questions

Which 1986 film, from the book of the same name by Umberto Eco, tells of a 10th century detective and monk?

Which instrument developed from African and Latin-American origins features in a modern orchestra as a bass xylophone?

Which country (capital Luanda) lies just south of Zaire?

Which airline has its home base in Atlanta, Georgia?

Which gemstone has the highest value per carat?