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.

Background Paragraph: It would be very unadvisable to place a can of soup over a campfire without venting the can. As the can heats up, it may explode. The kinetic-molecular theory explains why. The air inside the rigid can of soup is given more kinetic energy by the heat coming from the campfire. The kinetic energy causes the air molecules to move faster and they impact the container walls more frequently and with more force. The increase in pressure inside may eventually exceed the strength of the can and it will explode. An additional factor is that the soup may begin boiling which will then aid even more gas and more pressure to the inside of the can.
Story: A team of hikers split into two groups. Group Jones hiked north and camped there overnight. Group George went east. Both groups made campfires and heated cans of soups. Group Jones didn't make holes in the cans, so the cans exploded. The others heated their soup cans the right way, by venting them first.
Question: Which group's cans had the air molecules inside impact the container walls with more force?
Jones.

Background Paragraph: Storing large volumes of data When storing XML to either file or database, the volume of data a system produces can often exceed reasonable limits, with a number of detriments: the access times go up as more data is read, CPU load goes up as XML data takes more power to process, and storage costs go up. By storing XML data in Fast Infoset format, data volume may be reduced by as much as 80 percent.
Story: Ian had a busy day storing XML. At 4 PM, he stored 11100 Gigabytes to the database. At 5 PM, he stored 22200 Gigabytes to the database. At 6 PM, he stored 33300 Gigabytes to the database. At 7 PM, he got dinner. At 8 PM, he stored 44400 Gigabytes to the database. At 9 PM, he stored 55500 Gigabytes to the database. At 10 PM, he went to sleep to finish storing XML in the morning.
Question: What time did storage costs go up: 9 PM or 10 PM?
9 PM.

Background Paragraph: Another major cause of extinction is global warming , which is also known as global climate change. During the past century, the Earth's average temperature has risen by almost 1C (about 1.3F). You may not think that is significant, but to organisms that live in the wild and are constantly adapting to their environments, any climate change can be hazardous. Recall that burning fossil fuels releases gasses into the atmosphere that warm the Earth. Our increased use of fossil fuels, such as coal and oil, is changing the Earth's climate. Any long-term change in the climate can destroy the habitat of a species. Even a brief change in climate may be too stressful for an organism to survive. For example, if the seas increase in temperature, even briefly, it may be too warm for certain types of fish to reproduce.
Story: Two students studied for the biology exam. Ken studied about global warming, while Hank studied about Earth's oceans.
Question: Which student learned more about the increasing use of coal?
Ken.