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.

[EX Q]: Background Paragraph: There is worldwide concern about the relationship between climate change and the use of fossil fuels. Many scientists believe that increased use of these fuels (in vehicles and other gas-powered equipment) has the potential to irreversibly damage our environment. In addition to the environmental concerns, supplies of fossil fuels are finite, and because they are non-renewable energy sources, we will eventually need alternatives. New developments in batteries and other energy storage devices are being explored to help deal with these issues. Electrochemical processes are at the heart of these new technologies. 
Story: Two countries used different fuels as power sources for their activities. Alsacia used fossil fuels, while Lorena devised more advanced energy storage devices, therefore relying on electricity. 
Question: Which country contributed less to climate change?
[EX A]: Lorena.

[EX Q]: Background Paragraph: At the mid-oceanic ridges, two tectonic plates diverge from one another as new oceanic crust is formed by the cooling and solidifying of hot molten rock. Because the crust is very thin at these ridges due to the pull of the tectonic plates, the release of pressure leads to adiabatic expansion (without transfer of heat or matter) and the partial melting of the mantle, causing volcanism and creating new oceanic crust. Most divergent plate boundaries are at the bottom of the oceans; therefore, most volcanic activity on the Earth is submarine, forming new seafloor. Black smokers (also known as deep sea vents) are evidence of this kind of volcanic activity. Where the mid-oceanic ridge is above sea-level, volcanic islands are formed; for example, Iceland. 
Story: Hank and Dean studied plate tectonics in college. Hank learned more about divergent boundaries, while Dean read more about convergent boundaries. 
Question: Which student read less about volcanism and creating new oceanic crust?
[EX A]: Dean.

[EX Q]: Background Paragraph: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave frequencies. Wavelength is the distance between two corresponding points on adjacent waves. Wave frequency is the number of waves that pass a fixed point in a given amount of time. Electromagnetic waves with shorter wavelengths have higher frequencies and more energy. 
Story: David is experimenting with electromagnetic waves. He has four different waves to study, wave A, wave B, wave C, and wave D. In wave A, distance between two corresponding points on adjacent waves is greater than that of wave B.
In wave C, the number of waves that pass a fixed point in a given time is greater than that of wave D. 
Question: would wave A have higher or lower frequency than wave B?
[EX A]:
lower.