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The Karlsruhe Stadtbahn operates on the following route : Even before the opening of the Stadtbahn in 2010 the platforms of the stations were before were already 160 m long in order to handle the commuter trains to the  BASF  factory in  Ludwigshafen  ; this is longer than the existing Stadtbahn platforms which are normally 120 m long .
 city of headquarters: BASF, Ludwigshafen
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
 Entity Pairs:  BASF, Ludwigshafen 
Answer:
 city of headquarters: BASF, Ludwigshafen