Amanda went through archives of old Superman photos and discovered Lana Lang in the background of them. Utilizing the info Lex Luthor had collected from the Kent Farm she put the info into her computer, where she learned that Clark Kent was Superman. However, Luthor being unable to believe anyone with Superman's remarkable abilities would willingly choose to hide them. Luthor fired her for being wrong.
Amanda lived at 7324 Chesterfield Street. (Adventures of Superman #467)