user: Question: What school corporation has a mascot of Bruins and joined in 1971?
Columns: ['School', 'Mascot', 'School Corp.', 'Size', 'IHSAA Class (Football)', 'Year Joined', 'Other Conferences']
Types: ['text', 'text', 'text', 'real', 'text', 'text', 'text']
Sample row: ['Bishop Dwenger', 'Saints', 'R.C.D. FWSB', 1025.0, '3A (4A)', '1965', 'none (new school)']
SQL:

assistant: SELECT "School Corp." FROM "Table" WHERE "Year Joined" = '1971' AND "Mascot" = 'Bruins';