question: Was M1 employed by M2 , employed by M3 , employed by a film distributor , and employed by M4
query: SELECT count(*) WHERE {
  ?x0 a ns:film.film_distributor .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M4
  }