user: Question: How many institutions are shown for the football stadium of Mosaic Stadium?
Columns: ['Institution', 'Team', 'City', 'Province', 'Founded', 'Affiliation', 'Enrollment', 'Endowment', 'Football stadium', 'Capacity']
Types: ['text', 'text', 'text', 'text', 'real', 'text', 'real', 'text', 'text', 'real']
Sample row: ['University of British Columbia', 'Thunderbirds', 'Vancouver', 'BC', 1908.0, 'Public', 43579.0, '$1.01B', 'Thunderbird Stadium', 3500.0]
SQL:

assistant: SELECT COUNT("Institution") FROM "Table" WHERE "Football stadium" = 'Mosaic Stadium';