Table: tv_stations_4
Columns: region_served
city
channels_analog_digital
first_air_date
erp_analog_digital
haat_analog_digital_1
transmitter_location

Question: What region has a transmitter located at Mount Sugarloaf?
SQL: SELECT "region_served" FROM tv_stations_4 WHERE "transmitter_location" = 'mount sugarloaf'