Answer the following question given this paragraph: You can see how water for drinking is treated in Figure below . Treating drinking water requires at least four processes: 1. Chemicals are added to untreated water. They cause solids in the water to clump together. This is called coagulation. 2. The water is moved to tanks. The clumped solids sink to the bottom of the water. This is called sedimentation. 3. The water is passed through filters that remove smaller particles from the water. This is called filtration. 4. Chlorine is added to the water to kill bacteria and other microbes. This is called disinfection. Finally, the water is pure enough to drink. Q: When drinking water is treated, what is the term for when chemicals cause solids in the water to clump together? Choices: - clumping - oxidation - plasma - coagulation A:
coagulation
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Answer the following question given this paragraph: In some places, the oceanic crust comes up to a continent. The moving crust pushes that continent away from the ridge axis as well. If the moving oceanic crust reaches a deep sea trench, the crust sinks into the mantle. The creation and destruction of oceanic crust is the reason that continents move. Seafloor spreading is the mechanism that Wegener was looking for!. Q: What happens to the crust if the moving oceanic crust reaches a deep sea trench? Choices: - ocean volcano - it cleaves - forms a continent - sinks into mantle A:
sinks into mantle
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Answer the following question given this paragraph: In some countries, birth rates have fallen even lower than death rates. As result, their population growth rates are negative. In other words, the populations are shrinking in size. These populations have top-heavy population pyramids, like the one for Italy shown in Figure below . This is a new stage of the demographic transition, referred to as Stage 5. You might think that a negative growth rate would be a good thing. In fact, it may cause problems. For example, growth-dependent industries decline. Supporting the large aging population is also a burden for the shrinking younger population of workers. Q: What results when birth rates fall even lower than death rates? Choices: - disease - mutation - increased growth rate - negative growth rate A:
negative growth rate
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Answer the following question given this paragraph: Q: If environmental conditions deteriorate, many species can form protective what? Choices: - fibers - proteins - shells - cysts A:
cysts
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