Database: movielens
Question: What is the ID of actors that acted in the movies most viewed by audience with occupation 5?
SQL: SELECT T3.actorid FROM users AS T1 INNER JOIN u2base AS T2 ON T1.userid = T2.userid INNER JOIN movies2actors AS T3 ON T2.movieid = T3.movieid WHERE T1.occupation = 5 GROUP BY T2.movieid ORDER BY COUNT(T1.userid) DESC LIMIT 1