Question: How many acres is the district in Selma where  the most popular style of house in the Southern United States from the end of the American Civil War (1861–65) through the 1920s be found?
{'answer': '323', 'supporting_facts': [['Old Town Historic District (Selma, Alabama)', 0], ['Old Town Historic District (Selma, Alabama)', 3], ['Shotgun house', 0], ['Shotgun house', 1]]}