Wich factor could cause the fall the fall of a civilization

Three broad zones with different climates and resources shape russian life. they include:

My latest book, fightin’, prose short fiction, is a combination. there’s nothing about being indian in there. just stories of people. why shouldn’t i write about non-indians? i don’t have to dress anybody in feathers." how does ortiz's use of language in this excerpt set an informal tone? a. by using contractions and sentence fragments, ortiz makes this part of the interview feel more familiar and casual. c. by using the term "indian" rather than "native american," ortiz makes this part of the interview feel more combative or hostile. b. by employing first-person pronouns, ortiz makes this part of the interview more solemn and pessimistic. d. by asking a rhetorical question, ortiz makes this part of the interview objectively and intentionally funny and lighthearted.

When top-roping is used, how long should the rope be in order to protect the climber throughout the climb?