user: Question: What is the Callsign with an Area of Tamworth and frequency of 0 88.9?
Columns: ['Callsign', 'Area served', 'Frequency', 'Band', 'On-air ID', 'Purpose']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['2AAA', 'Wagga Wagga', '107.1', 'FM', '2AAA', 'Community']
SQL:

assistant: SELECT "Callsign" FROM "Table" WHERE "Area served" = 'Tamworth' AND "Frequency" = '0 88.9';