Were M2 , M3 , M4 , and M5 influenced by a Mexican person
SELECT count(*) WHERE {
?x0 a ns:people.person .
?x0 ns:people.person.nationality ns:m.0b90_r .
M2 ns:influence.influence_node.influenced_by ?x0 .
M3 ns:influence.influence_node.influenced_by ?x0 .
M4 ns:influence.influence_node.influenced_by ?x0 .
M5 ns:influence.influence_node.influenced_by ?x0
}