Question: Does the length of the tip influence the number of likes for hotel and travel business category?
SQL: SELECT T3.tip_length, SUM(T3.likes) AS likes FROM Categories AS T1 INNER JOIN Business_Categories AS T2 ON T1.category_id = T2.category_id INNER JOIN Tips AS T3 ON T2.business_id = T3.business_id WHERE T1.category_name = 'Hotels & Travel' GROUP BY T3.tip_length