Answer the following question given this paragraph: Q: The force that pulls objects toward the earth is what? Choices: - Friction - Magnetic force - Tension - gravity A:
gravity
(Question)
Answer the following question given this paragraph: Now consider what observer B sees happen to observer A. Observer B perceives light from the right reaching observer A before light from the left, because she has moved towards that flash lamp, lessening the distance the light must travel and reducing the time it takes to get to her. Light travels at speed c relative to both observers, but observer B remains equidistant between the points where the flashes were emitted, while A gets closer to the emission point on the right. From observer B's point of view, then, there is a time interval between the arrival of the flashes to observer A. From observer B's point of view, then, there is a time interval between the arrival of the flashes to observer A. In observer A's frame of reference, the flashes occur at different times. Observer B measures the flashes to arrive simultaneously relative to him but not relative to A. Now consider what observer A sees happening. She sees the light from the right arriving before light from the left. Since both lamps are the same distance from her in her reference frame, from her perspective, the right flash occurred before the left flash. Here a relative velocity between observers affects whether two events are observed to be simultaneous. Simultaneity is not absolute This illustrates the power of clear thinking. We might have guessed incorrectly that if light is emitted simultaneously, then two observers halfway between the sources would see the flashes simultaneously. But careful analysis shows this not to be the case. Einstein was brilliant at this type of thought experiment (in German, "Gedankenexperiment"). He very carefully considered how an observation is made and disregarded what might seem obvious. The validity of thought experiments, of course, is determined by actual observation. The genius of Einstein is evidenced by the fact that experiments have repeatedly confirmed his theory of relativity. In summary: Two events are defined to be simultaneous if an observer measures them as occurring at the same time (such as by... Q: The validity of thought experiments, of course, is determined by this? Choices: - predictive observation - theoretical observation - hypothetical observation - actual observation A:
(Answer)
actual observation
Ques: Answer the following question given this paragraph: In grazing , the predator eats part of the prey but does not usually kill it. You may have seen cows grazing on grass. The grass they eat grows back, so there is no real effect on the population. In the ocean, kelp (a type of seaweed) can regrow after being eaten by fish. Q: In grazing, a predator partially eats but does not kill what? Choices: - time - pack - predators - prey A:
Ans: prey
(Q).
Answer the following question given this paragraph: Plate tectonic processes explain why we see many types of geological activity where we do. Stresses build up in some locations. These stresses may cause folding or faulting. Earthquakes strike along all three types of plate boundaries. The most damaging earthquakes are shallow focus. People in earthquake-prone regions must be aware of the potential damage from earthquakes. Seismologists have scales for measuring earthquake intensity and magnitude. Cities in earthquake zones must build safe structures. They also have guidelines for being safe in earthquakes. Earthquakes are often associated with volcanoes. Volcanoes erupt at all types of plate boundaries except transform. Volcanic eruptions can be quiet or explosive. Volcanoes have a variety of shapes. The shapes range from large shields, to classic peaks, to small cones. Supervolcano eruptions are rare but extremely deadly. Volcanic activity creates unique landforms. Hot springs and geysers result when water meets hot rock below ground. Some geological activity, both earthquakes and volcanic eruptions, is located away from plate boundaries. Q: What causes a lot of geological activity on the earth? Choices: - landslides - weather - natural selection - plate tectonics A:
(A).
plate tectonics
Ques:Answer the following question given this paragraph: All living things reproduce to make the next generation. Organisms that do not reproduce will go extinct. As a result, there are no species that do not reproduce ( Figure below ). Some organisms reproduce asexually ( asexual reproduction ), especially single-celled organisms, and make identical copies (or clones) of themselves. Other organisms reproduce sexually ( sexual reproduction ), combining genetic information from two parents to make genetically unique offspring. Q: What process do all species use to make the next generation? Choices: - separation - differentiation - variation - reproduction A:

Ans:reproduction
Question: Answer the following question given this paragraph: Recall that air pollution is due to chemical substances and particles released into the air mainly by human actions. When most people think of air pollution, they think of the pollution outdoors. But it is just as easy to have indoor air pollution. Your home or school classroom probably doesn't get much fresh air. Sealing up your home reduces heating and cooling costs. But this also causes air pollution to stay trapped indoors. And people today usually spend a majority of their time indoors. So exposure to indoor air pollution can become a significant health risk. Q: What is caused by human actions that releases chemical substances and particles into the air? Choices: - CFO pollution - Improper Emissions - heavy pollution - air pollution A:
Answer:
air pollution