user: Question: Which Call sign has a Frequency of 102.5 FM?
Columns: ['Frequency', 'Call sign', 'Location', 'Name / Format', 'Owner']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['570 AM', 'CKGL', 'Kitchener', '570 News - news / talk', 'Rogers Communications']
SQL:

assistant: SELECT "Call sign" FROM "Table" WHERE "Frequency" = '102.5 FM';