user: Question:  how many winning team with circuit being Road America
Columns: ['Rnd', 'Race Name', 'Circuit', 'City/Location', 'Date', 'Pole position', 'Fastest lap', 'Winning driver', 'Winning team', 'Report']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'Marlboro Grand Prix of Miami Presented by Toyota', 'Homestead-Miami Speedway', 'Homestead, Florida', 'March 2', 'Alex Zanardi', 'Michael Andretti', 'Michael Andretti', 'Newman/Haas Racing', 'Report']
SQL:

assistant: SELECT COUNT("Winning team") FROM "Table" WHERE "Circuit" = 'Road America';