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: Antifreeze could also be called “antiboil” because it also raises the boiling point of the water in a car radiator. Hot weather combined with a hot engine can easily raise the temperature of the water in the radiator above 100 °C, which is the boiling point of pure water. If the water boils, it could cause the engine to overheat and become seriously damaged. However, if antifreeze has been added to the water, the boiling point is much higher. For example a 50 percent antifreeze solution has a boiling point of 129 °C. Unless the water gets hotter than this, it won’t boil and ruin the engine. 
Story: Rob is an auto mechanic. He was checking the radiators of his car and truck. He put antifreeze into the car radiator, but didn't put any antifreeze into the truck radiator. He was wondering how the vehicles would fare in coming hot weather. 
Question: Which vehicle's engine would less likely be damaged, car or truck?
car.

Background Paragraph: For example, your body has an internal thermostat. During a winter day, in your house a thermostat senses the temperature in a room and responds by turning on or off the heater. Your body acts in much the same way. When body temperature rises, receptors in the skin and the brain sense the temperature change. The temperature change triggers a command from the brain. This command can cause several responses. If you are too hot, the skin makes sweat and blood vessels near the skin surface dilate. This response helps decrease body temperature. 
Story: Recently, a man name Bob broke his leg, and has been commanded to stay inside and rest while it heals. His wife, Gretchen, has had to do most of the yard work, and it has been very hot outside. Bob has been watching his wife cut the grass and feels bad, noticing she looks tired, while he gets to sit inside in the air conditioning. 
Question: Which of the two most likely has their blood and sweat vessels dilated?
Gretchen.

Background Paragraph: When humans dig up and use fossil fuels, we have an impact on the carbon cycle ( Figure below ). This carbon is not recycled until it is used by humans. The burning of fossil fuels releases more carbon dioxide into the atmosphere than is used by photosynthesis. So, there is more carbon dioxide entering the atmosphere than is coming out of it. Carbon dioxide is known as a greenhouse gas , since it lets in light energy but does not let heat escape, much like the panes of a greenhouse. The increase of greenhouse gasses in the atmosphere is contributing to a global rise in Earth’s temperature, known as global warming or global climate change. 
Story: Greg is an environmental scientist. He wants to know how earth's atmosphere differed in two different time. To that end, he selected two time periods, time A and time B. Time A is set in the year one thousand when using fossil fuels was not very common. Time B is set in the year two thousand when fossil fuels are used in large quantities. 
Question: Would time A have lower or higher earth temperature than time B?

lower.