user: You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
You are given a background paragraph that describes one or more causal or qualitative relationships such as a relationship in economics or a scientific law and a story that makes use of the concepts or the relationship described in the provided paragraph. You are also given a question about the story that requires an understanding of the relationship described in the background paragraph and the story. You need to come up with an answer to the given question; the answer will be a span from either the question or the story. In order to correctly answer the given question, you need to understand the relationship mentioned in the background paragraph and should be able to use it to understand that in the story. Your answer can not consist of any word that is not mentioned in any of these: the background paragraph, the story, or the question. You can directly copy and paste a span from the story or the question while answering the given question.

Background Paragraph: A rise in price of a good or service almost always decreases the quantity demanded of that good or service. Conversely, a fall in price will increase the quantity demanded. When the price of a gallon of gasoline increases, for example, people look for ways to reduce their consumption by combining several errands, commuting by carpool or mass transit, or taking weekend or vacation trips closer to home. Economists call this inverse relationship between price and quantity demanded the law of demand. The law of demand assumes that all other variables that affect demand (which we explain in the next module) are held constant. 
Story: The AAA auto club does a weekly report on the prices of gas and diesel in various cities. Historically, the prices have be fairly stagnant, but this week their report garnered widespread attention as the prices of gas and diesel plunged from last week in Seattle by $0.40 each. However, just across the border in Vancouver, the cost of gas went up dramatically by $0.50. 
Question: Which city will have an increase in demand for gas?
Solution: Seattle.
Why? The first sentence in the background paragraph (A rise in price of a good or service almost always decreases the quantity demanded of that good or service) and the sentence in the story (as the prices of gas and diesel plunged from last week in Seattle by $0.40 each) answer this question.

New input: Background Paragraph: As shown here, pressure decreases to less than 25% of ground-level atmospheric pressure when we get to an altitude of about six miles. Since this is a common cruising altitude for commercial airplanes, pressurized cabins are needed for the comfort and survival of the passengers. This is because the density of the air decreases along with the decreasing air pressure, so there is less oxygen in a breath of air. You've probably noticed this effect in high-mountain areas, as it often feels harder to breath. 
Story: Marco is sitting at the bottom of a mountain and painting a picture of it. Lauren, Marco's friend, is sitting about halfway up the mountain and painting a picture of the horizon. The two will compare paintings after they complete their drawings and then will switch places and repeat the task. These two friends do this a couple times a year, and they always enjoy seeing how the other person paints the same object. 
Question: Who gets more oxygen per breath?
Solution:

assistant: Marco.