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.

Example Input: Background Paragraph: Bernoulli’s law explains how the wings of both airplanes and birds create lift that allows flight (see Figure below ). The shape of the wings causes air to flow more quickly — and air pressure to be lower — above the wings than below them. This allows the wings to lift the plane or bird above the ground against the pull of gravity. A spoiler on a race car, like the one in Figure below , works in the opposite way. Its shape causes air to flow more slowly — and air pressure to be greater — above the spoiler than below it. As a result, air pressure pushes the car downward, giving its wheels better traction on the track. 
Story: Rob is experimenting with how air pressure works. To that end, he has designed two tests. In the first test the air flow works as it would in an airplane wing. He labels it as case A. In the second test the air flow works as it would in a race car spoiler. He labels it as case B. He is surprised to see that air flow behaves differently in different situations. 
Question: Would case A have faster or slower air flow above it than case B?
Example Output: faster.

Example Input: Background Paragraph: Air pollution is harmful to human beings and other living things. About 22 million people die from air pollution each year. Breathing polluted air increases the risk of developing lung diseases such as asthma and lung cancer. Breathing bad air also increases the chances of dying from other diseases. Children are most likely to be affected by air pollution. That’s because their lungs are still developing and growing. Children also take in more air for their size than adults do. Some air pollutants damage the environment as well as the health of living things. The type of damage depends on the pollutant. Air pollution can also harm the environment. 
Story: Sarah and Sophie are sisters living in two different cities. Sarah lives in a very rural area with hardly any air pollution. Sophie lives in a heavily industrialized urban area with many factories and people driving cars to their destinations. This all leads to Sophie's city having a large amount of pollution going into the atmosphere. 
Question: Will the percentage of people with asthma be lower in Sophie's city or Sarah's city?
Example Output: Sarah's city.

Example Input: Background Paragraph: Another example of incomplete dominance is with sickle cell anemia, a disease in which a blood protein called hemoglobin is produced incorrectly. This causes the red blood cells to have a sickle shape, making it difficult for these misshapen cells to pass through the smallest blood vessels. A person that is homozygous recessive ( ss ) for the sickle cell trait will have red blood cells that all have the incorrect hemoglobin. A person who is homozygous dominant ( SS ) will have normal red blood cells. 
Story: Two sisters named Mary and Ann went in for a blood test and found out that Mary had sickle cell anemia. Ann was normal. 
Question: Which sister had a disease in which a blood protein called hemoglobin is produced incorrectly?
Example Output:
Mary.