instruction:
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."
question:
Background Paragraph: The Table above includes the ideal mechanical advantage of each class of lever. The mechanical advantage is the factor by which a machine changes the input force. The ideal mechanical advantage is the increase or decrease in force that would occur if there were no friction to overcome in the use of the machine. Because all machines must overcome some friction, the ideal mechanical advantage is always somewhat greater than the actual mechanical advantage of the machine as it is used in the real world. 
Story: John designed a hypothetical lever that would have ideal mechanical advantage. He labeled the lever as lever A. He then wanted to compare this lever with a real world lever, which he labeled as lever B. He intended to use these levers to increase force.
answer:
Which lever would have greater mechanical advantage, lever A or lever B?


question:
Background Paragraph: Air pollution is harmful to human beings and other living things. About 22 million people die from air pollution each year. Breathing polluted air increases the risk of developing lung diseases such as asthma and lung cancer. Breathing bad air also increases the chances of dying from other diseases. Children are most likely to be affected by air pollution. That’s because their lungs are still developing and growing. Children also take in more air for their size than adults do. Some air pollutants damage the environment as well as the health of living things. The type of damage depends on the pollutant. Air pollution can also harm the environment. 
Story: Tree city and Leaf city were the two biggest cities in Boulderland. Tree city burned lots of gas and other fossil fuels, while Leaf city was very protective towards its environment.
answer:
Which city caused less acid rain?


question:
Background Paragraph: The ozone layer is contained within the stratosphere. In this layer ozone concentrations are about 2 to 8 parts per million, which is much higher than in the lower atmosphere but still very small compared to the main components of the atmosphere. It is mainly located in the lower portion of the stratosphere from about 15–35 km (9.3–21.7 mi; 49,000–115,000 ft), though the thickness varies seasonally and geographically. About 90% of the ozone in Earth's atmosphere is contained in the stratosphere. 
Story: The ozone layer helps organisms by protecting them from Sun's ultraviolet radiation. To find the usefulness of ozone layer Mike wanted to see how much ozone are there in the atmosphere. He then collected three samples of atmosphere, sample A sample B, and sample C. Sample A was collected from the upper portion of the stratosphere. Sample B was collected from the lower portion of the stratosphere. Sample C was collected from the lower atmosphere.
answer:

Which sample would have higher concentration of ozone, sample A or sample B?