Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_8 (callsign VARCHAR, area_served VARCHAR, frequency VARCHAR)
### Question:
What is the Callsign with an Area of tamworth and frequency of 0 88.9?
### Answer:
SELECT callsign FROM table_name_8 WHERE area_served = "tamworth" AND frequency = "0 88.9"