Art literature what is the last line of the poem in which the famous line about mistah kurtz is used as an epigraph?

Read the excerpt from the building of manhattan. the heater cranked the blower handle to force air up through the fire and heat the rivets in the furiously burning bed of coals. he knew how hot the rivets were by the way their color changed. cherry-red rivets were 1,000 to 1,950 degrees fahrenheit. at the right moment he grabbed one in his tongs and tossed it to the catcher. which phrase cannot be changed in a paraphrase of this text? “the furiously burning bed of coals” “by the way their color changed” “1,000 to 1,950 degrees fahrenheit” “force air up through the fire and heat”