user: Please answer correctly the following question related to the paragraph below.   Which species can be regarded as the keystone species, species A, species B, or species C?  Mike is studying the predator prey relationship. He is specifically studying three species, species A, species B, and species C. Species A is a predator; species B is the prey; and species C is a plant species that species B lives on. Mike now needs to figure out how the predator prey relationship balance the ecosystem.  Hint: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species.
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Answer: species A


Please answer correctly the following question related to the paragraph below.   Which brother studied more about the influence sediments have on mantle melting?  Two brothers Syd and Dan went to college. Syd studied plate tectonics and mantle melting. His brother Dan got to study types of soil and pedology.  Hint: Mantle melting can come about three ways: (1) when the temperature rises, (2) if the pressure lowers (which lowers the melting point), and (3) if water is added, which lowers the melting point. Two of these (1 and 3) might explain why there are volcanoes at convergent plate boundaries the temperature of the subducting plate increases as it sinks into the hot mantle (1). Sediments lying on top of the subducting plate contain water. As the sediments subduct, the water rises into the overlying mantle material. This lowers the melting temperature of the mantle (3). When the mantle above the subducting plate melts, volcanoes form above it. This leads to volcanoes in an island arc or continental arc.
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Answer: Syd


Please answer correctly the following question related to the paragraph below.   Which city experienced less damage from rainfall?  Two coastal cities, Dune and Shore, got a Hurricane warning. The hurricane hit Dune city, but missed Shore city by 50 miles. The damage was horrendous.  Hint: So much rain falling so fast causes some of the damage from a hurricane. But a lot of the damage is caused by storm surge. Storm surge is very high water located in the low pressure eye of the hurricane. The very low pressure of the eye allows the water level to rise above normal sea level. Storm surge can cause flooding when it reaches land ( Figure below ). High winds do a great deal of damage in hurricanes. High winds can also create very big waves. If the large waves are atop a storm surge, the high water can flood the shore. If the storm happens to occur at high tide, the water will rise even higher.
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Answer:

assistant: Shore