question: Was a French person employed by M1 and employed by M2
query: SELECT count(*) WHERE {
  ?x0 a ns:people.person .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  ?x0 ns:people.person.nationality ns:m.0f8l9c
  }