[Q]: Keith is a physician with the city hospital. He noticed that reactions inside human body happen in different rates. He specifically noticed two cases, case A and case B. In case A enzymes were present, but in case B enzymes were not present. Given the paragraph above, please answer correctly the following question: In which case rate of chemical reactions would be lower, case A or case B? Hint: Enzymes increase the rate of chemical reactions by reducing the amount of activation energy needed for reactants to start reacting. One way this can happen is modeled in the Figure below . Enzymes aren't changed or used up in the reactions they catalyze, so they can be used to speed up the same reaction over and over again. Each enzyme is highly specific for the particular reaction is catalyzes, so enzymes are very effective. A reaction that would take many years to occur without its enzyme might occur in a split second with the enzyme. Enzymes are also very efficient, so waste products rarely form.
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[A]: case B

[Q]: Ryan explored two lakes; Big lake, and Arrow lake to the south. Arrow lake had a river flowing into it, while Big lake presented evidence of underwater geothermal activity. Many divers drowned in Arrow lake because of temperature shock. Given the paragraph above, please answer correctly the following question: Which lake had more of a temperature change concentrated over a small vertical interval? Hint: Thermoclines, or sudden changes in temperature. Where the air temperature is higher than the water temperature, shallow water may be warmed by the air and the sunlight but deeper water remains cold resulting in a lowering of temperature as the diver descends. This temperature change may be concentrated over a small vertical interval, when it is called a thermocline.[3][4] Where cold, fresh water enters a warmer sea the fresh water may float over the denser saline water, so the temperature rises as the diver descends.[3] In lakes exposed to geothermal activity, the temperature of the deeper water may be warmer than the surface water. This will usually lead to convection currents.[3]
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[A]: Arrow lake

[Q]: There are two neighboring towns in the middle of the United States with a river running through both of them. One town, Glenview, just installed a new set of levees due to concerns about the river flooding. The other town, Binnington, is located just upstream from Glenview and has not yet installed any flood protection. Given the paragraph above, please answer correctly the following question: Which town will experience a smaller increase of water when the river floods? Hint: People protect areas that might flood with dams. In dire situations, they use sandbags ( Figure below ). Dams are usually very effective, but high water levels sometimes cause a dam to break. In that case, flooding can be catastrophic. Flood waters can also overflow a dam. People may line a river bank with levees to protect against floods. These are high walls that keep the stream within its banks during floods. Flood protection in one location sometimes causes problems elsewhere. For example, a levee in one location may just force the high water upstream or downstream. This will lead to flooding in a different location. Sometimes water gets so high that the river must be allowed to flood.
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[A]: Glenview

[Q]: Tree city and Leaf city were the two biggest cities in Boulderland. Tree city burned lots of gas and other fossil fuels, while Leaf city was very protective towards its environment. Given the paragraph above, please answer correctly the following question: Which city exposed more people to lung cancer? Hint: 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.
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[A]:
Tree