5944
Among the most notable polluters in  Canada  in 2006 were electric power generators : ATCO Emera ( Nova Scotia Power ) Ontario Power Generation SaskPower and  TransAlta  mining companies : HudBay Minerals Teck Cominco Vale Inco and Xstrata oil and gas companies : Imperial Oil Shell Canada and Trans Canada oil sands companies : Syncrude and Suncor and the manufacturing enterprise SMC Canada .
 country of headquarters: Canada, TransAlta
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:  Canada, TransAlta 
Answer:
 country of headquarters: Canada, TransAlta