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: Mantle melting can come about three ways: (1) when the temperature rises, (2) if the pressure lowers (which lowers the melting point), and (3) if water is added, which lowers the melting point. Two of these (1 and 3) might explain why there are volcanoes at convergent plate boundaries the temperature of the subducting plate increases as it sinks into the hot mantle (1). Sediments lying on top of the subducting plate contain water. As the sediments subduct, the water rises into the overlying mantle material. This lowers the melting temperature of the mantle (3). When the mantle above the subducting plate melts, volcanoes form above it. This leads to volcanoes in an island arc or continental arc. 
Story: Two geologists studied the Earth's crust. Benny studied mantle melting, while Vinny studied more about crust displacement. 
Question: Which scientist observed more volcanoes forming?

A: Benny.
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Q: Background Paragraph: The balls used in squash are small rubber balls that can differ in terms of diameter, weight and softness. These features determine the speed and bouncing amplitude of the ball, with softer balls being generally slower than the harder balls. The temperature of the ball also affects the amount of bounce: the warmer the ball, the more it bounces.[3] Because cold squash balls have little bounce, the squash balls are hit multiple times at the beginning of a game to warm them up. It also means that a game becomes gradually faster as it advances and that softer balls may be too slow to be used in colder climates.[4]. 
Story: Thomas and Joseph, two experienced squash players, are having a disagreement about which types of squash balls they should use in their match. Both have different preferences for the type of ball used. Joseph prefers a ball that bounces less and travels more slowly. Thomas, on the other hand, prefers a ball that travels more quickly and bounces more. 
Question: Which player enjoys the speed of game more as it progresses?

A: Thomas.
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Q: Background Paragraph: Plants can grow as much as 50 percent faster in concentrations of 1,000 ppm CO2 when compared with ambient conditions, though this assumes no change in climate and no limitation on other nutrients. Elevated CO2 levels cause increased growth reflected in the harvestable yield of crops, with wheat, rice and soybean all showing increases in yield of 12–14% under elevated CO2 in FACE experiments.Increased atmospheric CO2 concentrations result in fewer stomata developing on plants which leads to reduced water usage and increased water-use efficiency. Studies using FACE have shown that CO2 enrichment leads to decreased concentrations of micronutrients in crop plants. This may have knock-on effects on other parts of ecosystems as herbivores will need to eat more food to gain the same amount of protein.The concentration of secondary metabolites such as phenylpropanoids and flavonoids. 
Story: Jerry and Gary each live in separate cities, but both run equally sized farms that grow the same produce. The cities they live in have very similar environments with the only difference being that the CO2 levels in Jerry's town are elevated, and in Gary's they are not. Jerry and Gary regularly talk on the phone and compare notes with each other since their farms are so similar. 
Question: Which person's crops will have more stomata?

A:
Gary's.
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