Which detail from "to build a fire" best supports the idea that survival was not guaranteed along the actual yukon trail? then it turned and trotted up the trail in the direction of the camp it knew, where were the other food providers and fire providers. his pace of four miles an hour had kept his heart pumping blood to the surface of his body and to all the extremities. but he was safe. toes and nose and cheeks would be only touched by the frost, for the fire was beginning to burn. a good idea, he thought, to sleep off to death. it was like taking an anesthetic. freezing was not so bad as people thought.

In the story, the newcomer was plainly cautioned and he was informed that it was "too cold to travel". This demonstrated it was not sheltered and survival was not ensured. Regardless of this notice, the newcomer took off.  

Toward the end of the story, he froze to death.

a caption indicating the purpose of the diagram

explanation:

(you didn't attach a copy of the poem, but i'm answering as best as i can)

since a simile compares two unlike things using like or as, it kind of gives an item the ability to do something it can't.

example: "the player was like a tiger on the field"

in this sentence, the simile conveys the idea that the player was fast and strong, like a tiger.