Table: radio_stations_27
Columns: frequency
callsign
brand
format
city_of_license
website
webcast

Question: Name the sum of frequecy with brand of exa fm
SQL: SELECT SUM("frequency") FROM radio_stations_27 WHERE "brand" = 'exa fm'

Question: Name the webcast for website of • and frequency of 103.3
SQL: SELECT "webcast" FROM radio_stations_27 WHERE "website" = '•' AND "frequency" = 103.3

Question: Name the lowest frequency for brand of radio manantial
SQL: SELECT MIN("frequency") FROM radio_stations_27 WHERE "brand" = 'radio manantial'