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.

Q: Background Paragraph: Protozoa generally feed by engulfing and digesting other organisms. As consumers, they have various roles in food chains and webs. Some are predators. They prey upon other single-celled organisms, such as bacteria. In fact, protozoa predators keep many bacterial populations in check. Other protozoa are herbivores. They graze on algae. Still others are decomposers. They consume dead organic matter. There are also parasitic protozoa that live in or on living hosts. For example, the protozoan that causes malaria lives inside a human host. For their part, protozoa are important food sources for many larger organisms, including insects and worms. 
Story: An astronaut has just landed on a new martian planet and encounters two different protozoa. The first protozoa he finds, protozoa X, is eating algae that is floating on top of water. The second protozoa, protozoa Y, is found eating bacteria. Upon further study, it is found that these are the only foods these two specific protozoa eat. 
Question: Which protozoa is a herbivore?

A: protozoa X.
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Q: Background Paragraph: Alkali, or Alkaline, soils are clay soils with high pH (> 8.5), a poor soil structure and a low infiltration capacity. Often they have a hard calcareous layer at 0.5 to 1 metre depth. Alkali soils owe their unfavorable physico-chemical properties mainly to the dominating presence of sodium carbonate, which causes the soil to swell[1] and difficult to clarify/settle. They derive their name from the alkali metal group of elements, to which sodium belongs, and which can induce basicity. Sometimes these soils are also referred to as alkaline sodic soils.
Alkaline soils are basic, but not all basic soils are alkaline. 
Story: Two brothers have a piece of land each, situated 2 miles from each other. Jim's land is not very fertile because it has clay soil with a high pH, while Bob's land has very fertile soil and has a good productivity on it. 
Question: Which of the two pieces of land has a high pH?

A: Jim's.
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Q: Background Paragraph: The Mercator projection is best within 15 degrees north or south of the equator. Landmasses or countries outside that zone get stretched out of shape. The further the feature is from the equator, the more out of shape it is stretched. For example, if you look at Greenland on a globe, you see it is a relatively small country near the North Pole. Yet, on a Mercator projection, Greenland looks almost as big the United States. Because Greenland is closer to the pole, the continent's shape and size are greatly increased. The United States is closer to its true dimensions. 
Story: Bob is looking at a map with Mercator projection to help him with his geography class. He noticed that Ecuador is within fifteen degrees north or south of the equator, but Norway is farther north of the equator. Bob starts to see how a country's location on a map affects how they look. 
Question: Would Norway's shape and size increase or decrease on a map?

A:
increase.
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