of roller coaster propulsion system propulsion of the roller coasters, which has the the lowest maximum speed?
Entity
m.04np8z
Lift hill
class class literal
amusement_parks.roller_coaster_propulsion_system amusement_parks.roller_coaster 0^^http://www.w3.org/2001/XMLSchema#int
amusement_parks.roller_coaster_propulsion_system amusement_parks.roller_coaster type.float
Roller Coaster Propulsion System Roller Coaster 0
none none argmin
amusement_parks.roller_coaster.propulsion amusement_parks.ride.max_speed
Propulsion Max Speed
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :amusement_parks.roller_coaster_propulsion_system . 
?x1 :type.object.type :amusement_parks.roller_coaster . 
{
SELECT (MIN(?y2) AS ?x2)  WHERE { 
?y0 :type.object.type :amusement_parks.roller_coaster_propulsion_system . 
?y1 :type.object.type :amusement_parks.roller_coaster . 
?y1 :amusement_parks.roller_coaster.propulsion ?y0 . 
?y1 :amusement_parks.ride.max_speed ?y2 . 
FILTER ( ?y0 != ?y1 && ?y0 != ?y2 && ?y1 != ?y2  )
}
}
?x1 :amusement_parks.roller_coaster.propulsion ?x0 . 
?x1 :amusement_parks.ride.max_speed ?x2 . 
FILTER ( ?x0 != ?x1 && ?x0 != ?x2 && ?x1 != ?x2  )
}
}
(ARGMIN amusement_parks.roller_coaster_propulsion_system (JOIN (R amusement_parks.roller_coaster.propulsion) amusement_parks.ride.max_speed))