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: The Human Immunodeficiency Virus ( HIV ) is the virus that causes Acquired Immunodeficiency Syndrome ( AIDS ). Most researchers believe that the HIV originated in sub-Saharan Africa during the 20th century. HIV is transmitted by sexual contact and by contact with infected bodily fluids, such as blood, semen, breast milk, and vaginal secretions. It is also passed from mother to fetus. HIV is now a pandemic , with an estimated (as of 2008) 38.6 million people now living with the disease worldwide. It is estimated that AIDS has killed more than 25 million people since it was first recognized in 1981. 
Story: Monica and Jill are two friends. They study and party together most of the time. One day Monica shared a needle with a drug addict at a party. She later found out that she'd been infected with HIV. Jill was scared and helped her as much as she could. 
Question: Which friend has a virus that is transmitted by sexual contact?

A: Monica.
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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: A thermometer is a device used to measure temperature. It is placed in contact with an object and allowed to reach thermal equilibrium with the object (they will have the same temperature). The operation of a thermometer is based on some property, such as volume, that varies with temperature. The most common thermometers contain liquid mercury, or some other liquid, inside a sealed glass tube. The liquid expands and contracts faster than the glass tube. Therefore, when the temperature of the thermometer increases, the liquid volume expands faster than the glass volume, allowing the liquid to rise in the tube. The positions of the liquid in the tube can then be calibrated for accurate temperature readings. Other properties that change with temperature can also be used to make thermometers; liquid crystal colors and electrical conductivity change with temperature, and are also relatively common thermometers. 
Story: A group of middle school students is measuring the temperature of various liquids for a chemistry lab using a mercury thermometer. They have a beaker of boiling water, a beaker of ice water, and a beaker of water at room temperature. 
Question: If the students move the thermometer from the room temperature water into the ice water will the mercury level go up or down?

A:
down.
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