TASK DEFINITION: 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.
PROBLEM: Background Paragraph: We all enjoy a cool dip in a swimming pool on a hot day, but we may not realize the work needed to keep that water safe and healthy. The ideal pH for a swimming pool is around 7.2. The pH will change as a result of many factors. Adjustment can be accomplished with different chemicals depending on the tested pH. High pH can be lowered with liquid HCl (unsafe material) or sodium bisulfate. The bisulfate anion is a weak acid and can dissociate partially in solution. To increase pH, use sodium carbonate. The carbonate anion forms an equilibrium with protons that results in some formation of carbon dioxide. 
Story: Tom and John are both pool owners. Tom prefers to use sodium bisulfate in his pool because he enjoys the smell. John, however, prefers using sodium carbonate in his pool because he believes it helps keep pests away. 
Question: Whose pool will have a lower pH?

SOLUTION: Tom.

PROBLEM: Background Paragraph: Biodiversity is determined by many things, and one of them is abiotic stress. If an environment is highly stressful, biodiversity tends to be low. If abiotic stress does not have a strong presence in an area, the biodiversity will be much higher.This idea leads into the understanding of how abiotic stress and endangered species are related. It has been observed through a variety of environments that as the level of abiotic stress increases, the number of species decreases. This means that species are more likely to become population threatened, endangered, and even extinct, when and where abiotic stress is especially harsh. 
Story: Italy had two distinct regions. Northern region where the animals are exposed to a lot of abiotic stress, and the southern region, where the animals experience almost no abiotic stress. 
Question: Which region had fewer endangered species?

SOLUTION: southern.

PROBLEM: Background Paragraph: Artworks are sold at affordable prices [6] ranging from £5 to £1500. For many of the works, the price goes up as the edition sells out. The edition runs range from 30 to 10,000 editions. Each work comes with a digital certificate that is “signed, numbered and authenticated by the artist” [7][8] Once an edition is sold out, collectors can resell their works in the online marketplace. 
Story: The prices of John's paintings started to rise immediately after the edition sold out. they used to cost $10 but now they sell for at least $200. john had 45 paintings in this edition. The prices of Mike's paintings are at $8 a piece, because his edition hasn't sold out yet. Mike's edition run was 250 editions. 
Question: Which painter was less successful at selling their paintings?

SOLUTION:
Mike.