É só ler com atenção, e, se você leu o livro, vai saber de cara, boa sorte mano :)
Answer:
The phrase "whose selfishness had not hesitated to buy its own peace at the price, perhaps, of the existence of the whole human race" best supports the the that humans posses the ability to be monstrous. The phrase shows how humans are only thinking of what they want and need and not about how their voices affect the people and things around them.
CCAC in order if you need any more help just ask !
Www.gradesaver.com/to-kill-a-mockingbird/q-and-a/explain-scouts-growing-up-260005
That is a chemical change if your talking about gases