Which class City of license of ferrum, virginia?
CREATE TABLE "radio_iq_full_power_affiliates" (
  "call_sign" text,
  "frequency_m_hz" real,
  "city_of_license" text,
  "erp_w" text,
  "class" text,
  "fcc_info" text
);
SELECT "class" FROM "radio_iq_full_power_affiliates" WHERE "city_of_license"='ferrum, virginia';