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.

[Q]: Background Paragraph: Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed, holding energy as rotational energy. When energy is extracted, the flywheel's rotational speed declines as a consequence of conservation of energy; adding energy correspondingly results in an increase in the speed of the flywheel.

Most FES systems use electricity to accelerate and decelerate the flywheel, but devices that directly use mechanical energy are under consideration. 
Story: Ben works with a flywheel, and has been instructed at various times to change the speeds based on certain conditions. He operates a device that gives or limits the flywheels energy by turning a crank left to give more energy, or right to decrease energy. 
Question: Will the flywheel go faster or slower if the crank is turned to the right?
[A]: slower.


[Q]: Background Paragraph: Unfortunately, the layer of good ozone is being destroyed by air pollution. The chief culprits are chlorine and bromine gases. They are released in aerosol sprays, coolants, and other products. Loss of ozone has created an ozone hole over Antarctica. Ozone depletion results in higher levels of UV radiation reaching Earth. In humans, this increases skin cancers and eye cataracts. It also disturbs the nitrogen cycle, kills plankton, and disrupts ocean food webs. The total loss of the ozone layer would be devastating to most life. Its rate of loss has slowed with restrictions on pollutants, but it is still at risk. 
Story: Two teams of researchers studied the environment in Antarctica. Team Black studied air pollution and the ozone layer, Team Red studied the water. 
Question: Which team observed higher levels of UV reaching Earth?
[A]: Black.


[Q]: Background Paragraph: Making these healthy lifestyle choices can also help prevent some types of cancer. In addition, you can lower the risk of cancer by avoiding carcinogens , which are substances that cause cancer. For example, you can reduce your risk of lung cancer by not smoking. You can reduce your risk of skin cancer by using sunscreen. How to choose a sunscreen that offers the most protection is explained below ( Figure below ). Some people think that tanning beds are a safe way to get a tan. This is a myth. Tanning beds expose the skin to UV radiation. Any exposure to UV radiation increases the risk of skin cancer. It doesn’t matter whether the radiation comes from tanning lamps or the sun. 
Story: Bob and Bill studied at the same university. While Bob got into studying nutrition, Bill ended up studying about cancer and how to prevent it. 
Question: Which student learned less about preventing some types of cancer?
[A]:
Bob.