What is associated with: a famous scene from this 1976 film was completely ad libbed the script simply read travis looks in the mirror?

Based on the clue 'a famous presidential saying a house this against ...', what is the answer? Based on the clue 'a famous quotation about this pear variety also ca...', what is the answer? Based on the clue 'a famous red coiffed clown or just any incompetent...', what is the answer? Based on the clue 'a famous rembrandt painting shows aristotle contem...', what is the answer? Based on the clue 'a famous series of concertos by vivaldi or frankie...', what is the answer? Who performed with 'a famous symbol of the pinkerton detective agency is an eye and the slogan we never do this'? Based on the clue 'a famous trademark of winston churchill was his fl...', what is the answer? Based on the clue 'a famous trio was made up of eugene istomin on pia...', what is the answer?