Which City has 600kw 500kw ERP ?
CREATE TABLE "main_transmitters" (
  "region_served" text,
  "city" text,
  "channels_analog_digital" text,
  "first_air_date" text,
  "erp_analog_digital" text,
  "haat_analog_digital_1" text,
  "transmitter_location" text
);
SELECT "city" FROM "main_transmitters" WHERE "erp_analog_digital"='600kw 500kw';