You will be given a definition of a task first, then some input of the task.
In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: Minnesota "Doc" West is sending money (each bill marked with an "E") to a 
boarding school in Boston in a post office at Santa Fe, New Mexico. After leaving the post 
office he is robbed by two bandits who take everything, including his money. He rides after
them on his horse, but is stopped when he sees a boy named Silver fall 
off his horse spooked by a rattlesnake. West shoots the rattlesnake's rattler off and it 
retreats into the bushes.  Silver's arm is dislocated, but West fixes it. Silver asks him if 
he's a doctor, but West declines.
Silver tells West that the bandits headed for Holysand, the nearest town. When they arrive 
in Holysand, they discover a fire in the middle of town set by Silver's stepfather and rancher,
Nathan Mitchell. Nathan argues with a rival rancher, Victor Baker about burning the bags of seed that Nathan bought. The argument is broken up by Sheriff
Roy Basehart and the local school teacher Denise Stark.
Nathan's ranch hand, Garvey orders Silver to clean it up.
West walks into the saloon turning everyone's head, because he is new. Instead of ordering 
whiskey he orders tea, causing everyone to ridicule him. Garvey offers him a seat and a round 
of poker. West wins a hand, but Garvey accuses him of cheating. The sheriff arrests West and 
locks him up and Garvey keeps West's money. Later that night Silver tells people about how West 
fixed his arm. When the sheriff tells West about his back pain, he suggests getting new boots. 
The next morning Nathan's daughter, Millie who West met in the post office,.
Output:
What is the full name of the man that the boy's stepfather is arguing with?