exxon mobil operates 37 oil refineries in 20 countries; in the usa, it owns and operates about 12,000 service stations
"world's 3rd largest company (2009 sales: $310 billion)
"exxon mobil operates 37 oil refineries in 20 countries; in the usa, it owns and operates about 12,000 service stations" What is the definition of "exxon mobil"?