CREATE TABLE "complete_formula_one_world_championship_" (
  "year" real,
  "entrant" text,
  "chassis" text,
  "engine" text,
  "points" real
);

Question: What is the earliest year that had a Lotus 49B chassis?
SQL: SELECT MIN("year") FROM "complete_formula_one_world_championship_" WHERE "chassis"='lotus 49b';