[Q]: John was pondering about what makes a chemical reaction faster or slower. To find the answer he did two tests, test A and test B. In test A he warmed up the reactants, but in test B he cooled down the reactants. To see a practical example of these tests he conducted two more tests, test C and test D. In test C he kept a food item in the refrigerator, but in test D he kept the same food item on the table top. In which test the particles of reactants would have lower energy, test A or test B? Hint: When the temperature of reactants is higher, the rate of the reaction is faster. At higher temperatures, particles of reactants have more energy, so they move faster. As a result, they are more likely to bump into one another and to collide with greater force. For example, food spoils because of chemical reactions, and these reactions occur faster at higher temperatures (see the bread on the left in the Figure below ). This is why we store foods in the refrigerator or freezer (like the bread on the right in the Figure below ). The lower temperature slows the rate of spoilage.
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[A]: test B

[Q]: Adam was playing tag football when one of his friends tagged him a bit too hard and caused him to tumble and fall. He noticed when he fell, he got a pretty bad cut in his knee. He decided to ignore the injury for now and keep playing. Later when he got home he realized the area of the cut was warm and swollen Will the blood vessels near Adam's injury have expanded or contracted? Hint: The body's second line of defense against pathogens includes the inflammatory response. If bacteria enter the skin through a scrape, the area may become red, warm, and painful. These are signs of inflammation. Inflammation is one way the body reacts to infections or injuries. Inflammation is caused by chemicals that are released when skin or other tissues are damaged. The chemicals cause nearby blood vessels to dilate, or expand. This increases blood flow to the damaged area, which makes the area red and slightly warm. The chemicals also attract white blood cells called neutrophils to the wound and cause them to leak out of blood vessels into the damaged tissue.
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[A]: expanded

[Q]: There are two planets, Glarnak and Bornak, that share the same atmospheric composition. The planets have nearly identical ecosystems and topography. The main difference between the two planets is the level of global warming on each planet. Glarnak is experiencing a strong impact from global warming. Bornak, though, is experiencing practically no effects of global warming. Which planet has more pollutants in the atmosphere? Hint: Pollutants also affect the atmosphere through their contribution to global warming. Global warming is an increase in the Earth's temperature. It is thought to be caused mostly by the increase of greenhouse gases like carbon dioxide. Greenhouse gases can be released by factories that burn fossil fuels. Over the past 20 years, burning fossil fuels has produced about three-quarters of the carbon dioxide from human activity. The rest of the carbon dioxide in the atmosphere is there because of deforestation, or cutting down trees ( Figure below ). Trees absorb carbon dioxide during cellular respiration, so when trees are cut down, they cannot remove carbon dioxide from the air.
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[A]: Glarnak

[Q]: The scientists examined both the Eastern and the Western slopes of the mountain. They reached the conclusion that the Western slope was inhabited by many more adult Tasmanian devils than the Eastern slope. Which slope had fewer devils climbing shrubs up 4 meters high? Hint: The Tasmanian devil is a nocturnal and crepuscular hunter, spending the days in dense bush or in a hole.[64] It has been speculated that nocturnalism may have been adopted to avoid predation by eagles and humans.[65] Young devils are predominantly crepuscular.[66] There is no evidence of torpor.[67] Young devils can climb trees, but this becomes more difficult as they grow larger.[68][69] Devils can scale trees of trunk diameter larger than 40 cm (16 in), which tend to have no small side branches to hang onto, up to a height of around 2.53 m (8.29.8 ft). Devils that are yet to reach maturity can climb shrubs to a height of 4 metres (13.1 ft), and can climb a tree to 7 m (23 ft) if it is not vertical.[70] Adult devils may eat young devils if they are very hungry, so this climbing behaviour may be an adaptation to allow young devils to escape.[71] Devils can also swim and have been observed crossing rivers that are 50 metres (160 ft) in width, including icy cold waterways, apparently enthusiastically.
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[A]:
Western