15721
IntercontinentalExchange Inc. said Wednesday it reached a deal that in effect sweetens the Atlanta energy exchange operator's bid to buy the  Chicago  Board of Trade putting more pressure on rival bidder the  Chicago Mercantile Exchange  .
 city of headquarters: Chicago, Chicago Mercantile Exchange
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "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} 
Answer:
 city of headquarters: Chicago, Chicago Mercantile Exchange