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In April 2011 it was awarded a five-year contract by the  Charlotte Area Transit System  (  CATS  ) for the exclusive right to sell advertising on the city's buses and light-rail vehicles .
 alternate names: Charlotte Area Transit System, CATS
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:  Charlotte Area Transit System, CATS 
Answer:
 alternate names: Charlotte Area Transit System, CATS