user: Question: What is the number of podiums for the races of 13/15?
Columns: ['Season', 'Series Name', 'Champion', 'Races †', 'Pole Positions', 'Wins', 'Podiums', 'Fastest Laps', 'Points', 'Margin (pts)']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1978.0, 'Shellsport F1 Series', 'Tony Trimmer', '8/12', '4', '5', '8', '5', '149', '56']
SQL:

assistant: SELECT "Podiums" FROM "Table" WHERE "Races †" = '13/15';