What is the number of contestants who are 5'7" and exactly 26 years of age?
CREATE TABLE "official_delegates" (
  "country" text,
  "contestant" text,
  "age" real,
  "height_cm" real,
  "height_ft" text,
  "hometown" text
);
SELECT COUNT("contestant") FROM "official_delegates" WHERE "height_ft"='5''7\"' AND "age"=26;