How many characters is by Babs Rubenstein?
CREATE TABLE "table1_10402018_1" (
  "character" text,
  "australia_new_zealand_sydney_first_run_melbourne_auckland" text,
  "london" text,
  "toronto_broadway" text,
  "brazil" text,
  "uk_tour" text,
  "us_tour" text,
  "italy_milan_rome_trieste" text
);
SELECT COUNT("london") FROM "table1_10402018_1" WHERE "us_tour"='Babs Rubenstein';