Sentence 1: Ken was at the gas station filling up his truck. 
 Sentence 3: While they were getting gas another guy tried to start a fight 
 Sentence 4:  Ken didn't know the guy but Tony did 
 Sentence 5:  Luckily Ken was able to talk the man out of fighting and the man left 
 Option 1: His friend Tony was also at the gas station. 
 Option 2: He was talking to his friend Tony on the phone.