who is the ship builder who constructed a ship with a draught less than 5.5 and length 53.0?
(AND boats.ship_builder (JOIN (R boats.ship.ship_builder) (AND (JOIN boats.ship.length_overall 53.0^^http://www.w3.org/2001/XMLSchema#float) (lt boats.ship.draught 5.5^^http://www.w3.org/2001/XMLSchema#float))))