[Q]: Given the background: In the U.S., the majority of electricity is produced by burning coal or other fossil fuels. This causes air pollution, acid rain, and global warming. Fossil fuels are also limited and may eventually run out. Like fossil fuels, radioactive elements are limited. In fact, they are relatively rare, so they could run out sooner rather than later. On the other hand, nuclear fission does not release air pollution or cause the other environmental problems associated with burning fossil fuels. This is the major advantage of using nuclear fission as a source of energy. and the situation: Marion county used coal and oil to produce electricity, while James county used nuclear energy for its electricity production. Both counties had a flourishing economy. Answer the following question: Which county caused less air pollution?
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[A]: James

[Q]: Given the background: As a star begins to run low on hydrogen, since the initial quantity has been fused into the denser helium gas, the core will contract due to gravity. The collapsing core increases temperature to the point that the star can begin to fuse helium into carbon. When that happens, the outer portion of the star expands greatly due to the higher temperature. The star can expand to 1000 times the diameter of the sun. At this point, the star is called a red giant . If our sun became a red giant, its surface would expand out past the orbit of Mars. Red giants are red because the surface of the star is cooler than white or blue stars, but remain highly visible because of their gigantic size. and the situation: John is an amateur astronomer. He recently found two stars, star A and star B. Upon observation, he figured out that star A is a blue star, but star B is a red giant. He had to do some research to find out the differences between them. Answer the following question: Which star would be more visible, star A or star B?
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[A]: star B

[Q]: Given the background: The two adrenal glands are located above the kidneys. Each gland has an inner and outer part. The outer part, called the cortex, secretes hormones such as cortisol, which helps the body deal with stress, and aldosterone, which helps regulate the balance of minerals in the body. The inner part of each adrenal gland, called the medulla, secretes fight-or-flight hormones such as adrenaline, which prepare the body to respond to emergencies. For example, adrenaline increases the amount of oxygen and glucose going to the muscles. You can see an animation of this response at the link below. and the situation: John is a biologist, who studies animal species of tundra biome. He noticed that they behave in certain way when they secrete hormones from adrenal glands' cortex. On the other hand, they behave some other way when they secrete hormones from adrenal glands' medulla. He termed the first process as process A and latter process as process B. Answer the following question: Which process would involve hormone adrenaline, process A or process B?
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[A]: process B

[Q]: Given the background: Beginning in the late 1970's, ozone depletion was recognized as a significant environmental issue. The most dramatic decrease in ozone occurs seasonally over the continent of Antarctica. The size and duration of the ozone hole steadily increased, with the largest hole recorded in 2006. Fortunately, most countries have recognized the danger of CFCs and dramatically curtailed their use in recent years. It is hoped that ozone depletion will slow and that the ozone layer may eventually be restored to its earlier levels. and the situation: Ben and Harry were studying about the climatic history of Earth. Ben was more attracted to learning about early Ice Ages, while Harry was curious about the Earth atmosphere and read about ozone depletion and its consequences. Answer the following question: Which person learned more about the size of the ozone hole over Antarctica?
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[A]:
Harry