Jack gets to the bus station very early. The bus for Beijing is leaving   at twelve. He sees many people at the station. Some are waiting in line, and others are walking around. Jack looks around but there is no room   for him to sit in. He walks into a restaurant. He looks up at the clock there. It's only 11:30. Then he finds a seat and sits down. At that time, Tom, one of his friends, comes in and sits in front of him. They talk and drink. After a while, Jack looks up at the clock again. "Oh, my God. It's still   11:30. The clock doesn't work at all." Jack becomes very sad because he misses   the bus. Tom is   _  .
a policeman a businessman Jack's brother Jack's friend