How long does Yelp_Business no.1 open on Tuesdays?
"How long" and "how much time" are synonyms; how much time does this business open refers to subtract(closing_time, opening_time); Yelp_Business no.1 refers to business_id = 1; Tuesdays refers to day_of_week = 'Tuesday'
SELECT T1.closing_time - T1.opening_time AS "opening hours" FROM Business_Hours AS T1 INNER JOIN Days AS T2 ON T1.day_id = T2.day_id WHERE T2.day_of_week LIKE 'Tuesday' AND T1.business_id = 1