who is the driver with the engine era 1.5 l6 s and the chassis is era b?
CREATE TABLE "entries" (
  "driver" text,
  "entrant" text,
  "constructor" text,
  "chassis" text,
  "engine" text,
  "tyre" text
);
SELECT "driver" FROM "entries" WHERE "engine"='era 1.5 l6 s' AND "chassis"='era b';