How many rounds were there of the Bosch Spark Plug Grand Prix?
CREATE TABLE "races" (
  "rnd" text,
  "race_name" text,
  "circuit" text,
  "city_location" text,
  "date" text,
  "pole_position" text,
  "fastest_lap" text,
  "winning_driver" text,
  "winning_team" text,
  "report" text
);
SELECT COUNT("rnd") FROM "races" WHERE "race_name"='Bosch Spark Plug Grand Prix';