Read the passage from part 1 of “to build a fire.” he knew that at fifty below spittle crackled on the snow, but this spittle had crackled in the air. undoubtedly it was colder than fifty below—how much colder he did not know. but the temperature did not matter. he was bound for the old claim on the left fork of henderson creek, where the boys were already. they had come over across the divide from the indian creek country, while he had come the roundabout way to take a look at the possibility of getting out logs in the spring from the islands in the yukon. what excerpt from the passage reveals the environment of the story?

The environment of a story is the physical location where the subjects are, this is revealed on the excerpt: "On the left fork of Henderson Creek, where the boys were already, they had come over across the divide from the Indian Creek country". This section tells us the geographical location where the story takes place. We also know the temperature is below fifty degrees in this story.

I would contend that the right answer is actually "at fifty below."

Explanation: Just to elaborate a little on the answer, it can be added that on this excerpt from Jack London's short story the character is on his way to Henderson Creek, but the narrator is not describing this area yet. The only direct and precise reference to the physical environmental conditions of the story at this point is the one about the temperature. This suggests that the character is in an extremely cold landscape.  

im not sure about this one