For which film did Alan Arkin win the Oscar for Best Supporting Actor?

For which film did Morgan Freeman win the Oscar for Best Supporting Actor? Who won the Oscar for Best Supporting Actor for 'Syriana'? For which film did George Clooney win the Oscar for Best Supporting Actor? Who won the Oscar for Best Supporting Actor for 'Little Miss Sunshine'? Who won the Oscar for Best Supporting Actor for 'No Country for Old Men'? For which film did Javier Bardem win the Oscar for Best Supporting Actor? Who won the Oscar for Best Supporting Actor for 'The Dark Knight'? For which film did Heath Ledger win the Oscar for Best Supporting Actor?