[Q]: I read this background article the other day: Inhaling is an active movement that results from the contraction of a muscle called the diaphragm. The diaphragm is large, sheet-like muscle below the lungs (see Figure below ). When the diaphragm contracts, the ribcage expands and the contents of the abdomen move downward. This results in a larger chest volume, which decreases air pressure inside the lungs. With lower air pressure inside than outside the lungs, air rushes into the lungs. When the diaphragm relaxes, the opposite events occur. The volume of the chest cavity decreases, air pressure inside the lungs increases, and air flows out of the lungs, like air rushing out of a balloon. I am facing a new situation today: Keith is a physician in a local hospital. He is treating a patient with respiratory problem. He looked at two different states of the patient's diaphragm, state A and state B. In state A the the diaphragm contracted, but in state B the diaphragm relaxed. He now needs to figure out other phenomena related to this. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: When would the ribcage expand, state A or state B?
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[A]: state A

[Q]: I read this background article the other day: With shade applications, crops are purposely raised under tree canopies within the shady environment. The understory crops are shade tolerant or the overstory trees have fairly open canopies. A conspicuous example is shade-grown coffee. This practice reduces weeding costs and improves coffee quality and taste. The shade does not necessarily translate into lost or reduced yields. This is because the rate of photosynthesis hardly increases once the light intensity is over about one tenth that of direct overhead sunlight and declines with increasing light intensity. This means that shaded plants can grow well. Planting more than one level of vegetation can increase total photosynthesis and overall yields. I am facing a new situation today: Two coffee farms used different methods to grow coffee. Hill farm grown coffee conventionally, while Valley farm is into shade-grown coffee production. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which farm had fewer understory shade tolerant crops?
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[A]: Hill

[Q]: I read this background article the other day: Some materials have negative heats of solution; the dissolution of one of these solutes in water is an exothermic process. Heat is released, causing a net increase in the temperature of the solution. Conversely, other substances have positive heats of solution. For example, the dissolution of potassium nitrate in water is an endothermic process. The resulting absorption of energy causes the solution to become colder. Calculations involving heats of solutions follow the same basic approach that we have used with other enthalpy problems. I am facing a new situation today: A scientist is in the lab testing mixing water with different chemicals. While working with chemical A he notes that the water becomes colder after combining them. With chemical B the water becomes much warmer. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Given he adds a new chemical, chemical C and notes that it is an exothermic process, will the temperature have increased or decreased?
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[A]: decreased

[Q]: I read this background article the other day: Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. Nitrogen is a fertilizer in the water. Since there is a lot of nitrogen, it causes algae to grow out of control. Pictured below is a pond covered with algae ( Figure below ). Algae use up carbon dioxide in the water. After the algae die, decomposers break down the dead tissue. The decomposers use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico ( Figure below ). The U.S. states outlined on the map have rivers that drain into the Gulf of Mexico. The rivers drain vast agricultural lands. The water carries fertilizer from these areas into the Gulf. I am facing a new situation today: Greg is studying the environmental impact of agriculture. He noticed that in his own state a lake near agricultural lands has been declared as a dead zone. For his study Greg labeled this zone as zone A. Then he found near a national park in his state a lake is not declared as a dead zone. To further his study he labeled this zone as zone B. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would zone A see less or more organisms than zone B?
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[A]:
less