Who was the network who had Ken Squier as a host and 13.9 million viewers?
CREATE TABLE "cbs_era_1979_2000" (
  "year" real,
  "network" text,
  "lap_by_lap" text,
  "color_commentator_s" text,
  "pit_reporters" text,
  "host" text,
  "ratings" text,
  "viewers" text
);
SELECT "network" FROM "cbs_era_1979_2000" WHERE "host"='ken squier' AND "viewers"='13.9 million';