user: Question: Which long range AM station has the lowest frequency and includes a webcast of listen live, was licensed in the city of Monterrey, and uses the Callsign of XET?
Columns: ['Frequency', 'Callsign', 'Brand', 'City of License', 'Website', 'Webcast']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [680.0, 'KKYX', 'Country Legends 680', 'San Antonio', 'kkyx.com', 'listen live']
SQL:

assistant: SELECT MIN("Frequency") FROM "Table" WHERE "Webcast" = 'listen live' AND "City of License" = 'Monterrey' AND "Callsign" = 'XET';