For which film did Kate Winslet win the Oscar for Best Actress?

For which film did Helen Mirren win the Oscar for Best Actress? Who won the Oscar for Best Actress for 'La Vie en Rose'? For which film did Marion Cotillard win the Oscar for Best Actress? Who won the Oscar for Best Actress for 'The Reader'? Who won the Oscar for Best Actress for 'The Blind Side'? For which film did Sandra Bullock win the Oscar for Best Actress? Who won the Oscar for Best Actress for 'Black Swan'? For which film did Natalie Portman win the Oscar for Best Actress?