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In the  United States  General Motors  Duke Energy  and others have lined up in favor of European-style quotas leading many environmentalists and experts to question whether these companies would be required to do enough to change their business practices in ways that create an effective transition to a cleaner environment .
 country of headquarters: United States, Duke Energy
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:  United States, Duke Energy 
Answer:
 country of headquarters: United States, Duke Energy