What model has a total produced more than 5 and a prime move of 12-251c?
CREATE TABLE "4_axle_units" (
  "model" text,
  "build_date" text,
  "total_produced" real,
  "wheel_arrangement" text,
  "prime_mover" text,
  "power_output" text
);
SELECT "model" FROM "4_axle_units" WHERE "total_produced">5 AND "prime_mover"='12-251c';