Did M1 , M2 , M3 , and M4 employ M0 's actor
SELECT count(*) WHERE {
?x0 ns:film.actor.film/ns:film.performance.character M0 .
M1 ns:business.employer.employees/ns:business.employment_tenure.person ?x0 .
M2 ns:business.employer.employees/ns:business.employment_tenure.person ?x0 .
M3 ns:business.employer.employees/ns:business.employment_tenure.person ?x0 .
M4 ns:business.employer.employees/ns:business.employment_tenure.person ?x0
}