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: Because of human activities, there is more carbon dioxide in the atmosphere today than in the past hundreds of thousands of years. Burning fossil fuels and has released great quantities of carbon dioxide into the atmosphere. Cutting forests and clearing land has also increased carbon dioxide into the atmosphere because these activities reduce the number of autotrophic organisms that use up carbon dioxide in photosynthesis. In addition, clearing often involves burning, which releases carbon dioxide that was previously stored in autotrophs. 
Story: John has been hearing about climate change for last couple of years. He wants to understand the science behind climate change. For that, he picked up two eras in earth's history, era A and era B. Era A was hundred thousand years ago, and era B is in the present day. He now wants to compare these to eras to understand the change in climate better. 
Question: Which era would have seen less fossil fuel burning, era A or era B?

A: era A.
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Q: Background Paragraph: If all the other factors influencing humidity remain constant, at ground level the relative humidity rises as the temperature falls. This is because less vapor is needed to saturate the air, so vapor condenses as the temperature falls. In normal conditions, the dew point temperature will not be greater than the air temperature because relative humidity cannot exceed 100%.[4]. 
Story: Sam lived in Chicago for many years and experienced those high humidity days during the summer, the Indian summers in October and harsh and humid winters, so he decided to move to San Diego, in a warmer and much dryer climate. 
Question: Which city has less fog during summer?

A: San Diego.
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Q: Background Paragraph: During May, June, and July, the Northern Hemisphere is exposed to more direct sunlight because the hemisphere faces the Sun. The same is true of the Southern Hemisphere in November, December, and January. It is Earth's axial tilt that causes the Sun to be higher in the sky during the summer months, which increases the solar flux. However, due to seasonal lag, June, July, and August are the warmest months in the Northern Hemisphere while December, January, and February are the warmest months in the Southern Hemisphere. 
Story: Tim and Allen were two pen pals, Tim lived in Canada, while Allen lived in Australia. they were chatting about the weather and the fact that their two countries are situated in two different hemispheres. 
Question: Which person experiences warmer weather in August, Tim or Allen?

A:
Tim.
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