In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.
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Question: Question: Mona lives in a nation that uses a lot of fossil fuels. What would happen to her countries levels of air pollution if they were to decrease their usage?
Answer: decrease

Answer: Because richer nations use more fossil fuels, they also cause more air pollution and global warming than poorer nations do.

Question: Question: A population of squirrels in a local forest had less food available to them this spring than they did last spring. During which spring will more squirrels leave the area to live somewhere else?
Answer: this spring

Answer: Low food supply or a lack of space can lower birth rates, increase death rates, or lead to emigration.

Question: Question: Rich was examining a cliff face. Which part of the cliff is younger, geologically speaking?
Answer: the top

Answer:
The upper rock layers are much younger.