How many times was the time 20' 05.19 112.703mph on Thurs Aug 26th?
CREATE TABLE "2010_senior_manx_grand_prix_practice_tim" (
  "rank" real,
  "rider" text,
  "sat_21_aug" text,
  "mon_23_aug" text,
  "tues_24_aug" text,
  "wed_25_aug" text,
  "thurs_26_aug" text,
  "fri_27_aug" text,
  "sat_28_aug" text
);
SELECT COUNT("sat_21_aug") FROM "2010_senior_manx_grand_prix_practice_tim" WHERE "thurs_26_aug"='20'' 05.19 112.703mph';