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.
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Question: Background Paragraph: Alberta's electrical demand varies throughout the day and across the seasons. When individuals are fixing supper and using home appliances, demand for power goes up, as it does during heat waves and cold snaps. It tapers off during spring and fall. Like other mechanical devices, generators fail from time to time. If they are wind-powered, their output varies with the wind.
Story: It has been a weird week in the neighborhood. On Monday, there was a heat wave. On Tuesday, a cold snap happened. On Wednesday, everybody was using their ovens to bake cakes for the contest. On Thursday, everybody stayed home to do nothing but pray. On Friday, everybody went to the park to play in a soccer tournament and sleep in tents . On Saturday, there was another heat wave. On Sunday, another cold snap happened.
Question: What day did demand for power go up: Tuesday or Thursday?

Answer: Tuesday.

Question: Background Paragraph: Baker's yeast is the common name for the strains of yeast commonly used in baking bread and bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. Baker's yeast is of the species Saccharomyces cerevisiae,[1] and is the same species (but a different strain) as the kind commonly used in alcoholic fermentation, which is called brewer's yeast.[2] Baker's yeast is also a single-cell microorganism found on and around the human body.
Story: the students used yeasts in two different experiments: they baked bread using baker's yeast, and made beer, using brewer's yeast. They learned a lot about sugars and chemistry.
Question: Which yeast is better for bakery products?

Answer: baker's yeast.

Question: Background Paragraph: Each radioactive isotope has a characteristic decay time periodthe half-lifethat is determined by the amount of time needed for half of a sample to decay. This is an exponential decay process that steadily decreases the proportion of the remaining isotope by 50% every half-life. Hence after two half-lives have passed only 25% of the isotope is present, and so forth.
Story: David was working in his chemistry lab. He selected two isotopes, sample A and sample B. Sample A had longer half-life, but sample B had shorter half-life. After some time he checked sample A when its one half-life had passed. He noted it as sample A1. Then he came back to see it again when two half-lives had passed. He noted it as sample A2.
Question: Would sample A2 have less or more isotopes than sample A1?

Answer:
less.