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.
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Question: Background Paragraph: The mechanical advantage of a machine is the factor by which it changes the force applied to the machine. Many machines increase the force applied to them, and this is how they make work easier. Compound machines tend to have a greater mechanical advantage than simple machines. That’s because the mechanical advantage of a compound machine equals the product of the mechanical advantages of all its component simple machines. The greater the number of simple machines it contains, the greater its mechanical advantage tends to be. 
Story: David was studying the processes involved in a machine. He collected a simple machine. He tagged it as case A. To compare it with compound machines, he collected two compound machines, case B and case C. Case B is a compound machine with few simple machines. And, case C is a compound machine with many simple machines. 
Question: Would case B have greater or smaller mechanical advantage than case A?

Answer: greater.


Question: Background Paragraph: Weather is a set of all the phenomena occurring in a given atmospheric area at a given time. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate is the term for the average atmospheric conditions over longer periods of time. When used without qualification, "weather" is understood to be the weather of Earth. 
Story: David was interested in climate change issues. He realized that to understand climate change issues he first needed to distinguish between the terms weather and climate. To that end, he labeled weather as term A. Then he labeled climate as term B. He found it easier to understand their differences in that way. 
Question: Would term A change less or more frequently than term B?

Answer: more.


Question: Background Paragraph: Another obvious change that occurs during puberty is rapid growth. This is called the adolescent growth spurt . In boys, it is controlled by testosterone. The rate of growth usually starts to increase relatively early in puberty. At its peak rate, growth in height is about 10 centimeters (almost 4 inches) per year in the average male. Growth generally remains rapid for several years. Growth and development of muscles occur toward the end of the growth spurt in height. Muscles may continue to develop and gain strength after growth in height is finished. 
Story: Two researches studied adolescents during puberty. Tim studied males, while Dan studied females. 
Question: Which researcher didn't observe that the growth spurt is triggered by testosterone?

Answer:
Dan.