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 need to come up with a question about the story that requires an understanding of the relationship described in the background paragraph. The generated question should not be answerable without both the background and story. Write a question about the story that requires a relationship in the background paragraph to answer. Check whether your question requires both the background paragraph and the story to answer. If your question can be answered by only one of these, try to rewrite your question so that it requires both. Note that "flipping" a word in the question can give rise to a new question where the answer will be different from the original question. Often, "flipping" a word gives rise to flipping the direction of the relationship, for example, from "increase" to "decrease."
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Question: Background Paragraph: In exercises such as weight lifting, skeletal muscle contracts against a resisting force (see Figure below ). Using skeletal muscle in this way increases its size and strength. In exercises such as running, the cardiac muscle contracts faster and the heart pumps more blood. Using cardiac muscle in this way increases its strength and efficiency. Continued exercise is necessary to maintain bigger, stronger muscles. If you don’t use a muscle, it will get smaller and weaker—so use it or lose it. 
Story: David got five exercise tips from his personal trainer, tip A, tip B, tip C, tip D, and tip E. Tip A involves weight lifting, but tip B does not involve weight lifting. Tip C involves running, but tip D does not involve running. Finally, tip E does not involve any exercise at all. David has to find out which tips are most useful for him.

Answer: In which tip the cardiac muscle would be more efficient, tip C or tip D?


Question: Background Paragraph: When you add sugar to a cold drink, you may stir it to help the sugar dissolve. If you don’t stir, the sugar may eventually dissolve, but it will take much longer. Stirring is one of several factors that affect how fast a solute dissolves in a solvent. Temperature is another factor. A solid solute dissolves faster at a higher temperature. For example, sugar dissolves faster in hot tea than in ice tea. A third factor that affects the rate of dissolving is the surface area of the solute. For example, if you put granulated sugar in a glass of ice tea, it will dissolve more quickly than the same amount of sugar in a cube. That’s because granulated sugar has much more surface area than a cube of sugar. You can see videos of all three factors at these URLs. 
Story: Justin and Alejandro are conducting a chemical experiment involving sodium hydroxide. A key part of the reaction is ensuring that the sodium hydroxide is dissolved in water before adding the other materials. Justin adds the sodium hydroxide to reaction A, and begins stirring the mixture with a spoon. Alejandro also adds sodium hydroxide to his reaction, reaction B, but doesn't stir it because he is lazy.

Answer: Whose sodium hydroxide, Justin's or Alejandro's, will dissolve faster?


Question: Background Paragraph: Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. Nitrogen is a fertilizer in the water. Since there is a lot of nitrogen, it causes algae to grow out of control. Pictured below is a pond covered with algae ( Figure below ). Algae use up carbon dioxide in the water. After the algae die, decomposers break down the dead tissue. The decomposers use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico ( Figure below ). The U.S. states outlined on the map have rivers that drain into the Gulf of Mexico. The rivers drain vast agricultural lands. The water carries fertilizer from these areas into the Gulf. 
Story: Two farmer's associations used different agricultural methods when growing crops. Bold farm used lots of fertilizers over the years, while Shallow farm used organic methods combined with methods from permaculture.

Answer:
Which farm causes fewer algae to grow out of control?