What tyres have 1 point and an ensign n177 chassis?
CREATE TABLE "complete_world_championship_formula_one_" (
  "year" real,
  "chassis" text,
  "engine_s" text,
  "tyres" text,
  "points" text
);
SELECT "tyres" FROM "complete_world_championship_formula_one_" WHERE "points"='1' AND "chassis"='ensign n177';