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."

[Q]: Background Paragraph: Many chemicals that were once commonly used were later found out to be harmful to the environment , to human health, or both. The element lead was once a common additive to gasoline and to paint. Plumbing pipes were once typically made of lead. Only since the 1970s has the danger of lead become apparent. It causes brain damage and small children (who often chewed on objects painted with lead-based paint) are particularly susceptible. The use of lead in gasoline, paint, and plumbing pipes is now banned and new materials are being developed to replace the hazardous lead components. 
Story: Tom and Bob grew up next to each other, but their houses were very different. Tom's childhood home was built in 1935 and had never been renovated since then, but Bob's home was built in 1994 and had been regularly updated to be more modern. They both enjoyed spending time at one another's houses because they seemed so different from their own home.
[A]: Which child less likely was exposed to lead in their drinking water?


[Q]: Background Paragraph: For example, if a circuit has a potential difference of 100 volts and it is intended for the circuit to contain a 100 ohm resistance, then the wires carrying the current for this circuit will be designed for 1.0 amp. If that 100 ohm resistance is suddenly cut out of the circuit and only 0.10 ohm resistance remains, then the voltage will push 1000 amps of current through the circuit. This current overheats the wires and may damage the circuits or start a fire in the walls or the appliance. There are many possible causes of a short circuit, one possible cause could be something overheating, melting wires, and thereby fusing the circuit closed, bypassing the resistance. Another cause might be something damaging the insulation of a wire, allowing the incoming and grounds wires to touch. In any case, once the resistance is lost, the voltage pushes a huge amount of charge through the wires causing them to overheat. 
Story: John is preparing for a do it yourself science project. First, he made a circuit with adequate resistance. He labeled that state of the circuit as circuit A. Then he lowered the resistance. He called that new state of the circuit as circuit B. While he was doing all this, his friend Keith showed up with another circuit, circuit C. But that circuit's insulation was damaged.
[A]: Which circuit would be less prone to short circuit, circuit A or circuit C?


[Q]: Background Paragraph: About 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, in which water erodes the limestone over thousands to millions of years. Most cave systems are through limestone bedrock. 
Story: Peter visited two mountain ranges last summer. The Ozarks in Missouri, and the Colorado Rockies. He loved both ranges, but liked the caves systems and blue holes in the Ozarks a bit more.
[A]:
Which mountains have more caves?