Can someone please help me with this?

Then she heard his step on the stair away down on the first flight, and she turned white for just a moment. the phrase "she turned white for just a moment" is mainly used to show that della has very fair skin. is afraid of jim's reaction. is beginning to get an illness. had become extremely angry.

(1) fire extended humans’ geographical boundaries by allowing them to travel into regions that were previously too cold to explore. (2) it also kept predators away, allowing early humans to sleep securely. (3) fire, in fact, has been a significant factor in human development and progress in many ways. (4) other obvious benefits of fire are its uses in cooking and in hunting. (5) probably even more important, however, is that learning to control fire allowed people to change the very rhythm of their lives. (6) before fire, the human daily cycle coincided with the rising and setting of the sun. (7) with fire, though, humans gained time to think and talk about the day’s events and to prepare strategies for coping with tomorrow. the sentence that expresses the main idea is: (type the number of the sentence. then click “go.”)

Which sentence in this excerpt from leo tolstoy’s the death of ivan ilyich suggests that ivan ilyich and his wife couldn’t even agree on how to raise their children?