| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.04 |
| Score | 0% | 61% |
Water freezing or boiling is an example of which of the following?
heating |
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phase transition |
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sublimation |
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cooling |
A substance undergoes a phase transition when it moves from one state of matter to another, for example, when water freezes or boils.
Arteries carry __________ blood at __________ pressure.
deoxygenated, high |
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oxygenated, low |
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deoxygenated, low |
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oxygenated, high |
Veins carry blood back to the heart from the body. While arteries are thick-walled because they carry oxygenated blood at high pressure, veins are comparatively thin-walled as they carry low-pressure deoxygenated blood. Like the heart, veins contain valves to prevent blood backflow.
An asteroid belt holds many of the asteroids in our solar system. It is located between the orbits of which planets?
Mars and Earth |
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Mars and Jupiter |
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Mercury and Venus |
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Jupiter and Saturn |
The solar system also contains over a million rocky fragments of at least 1km in diameter called asteroids as well as millions more with smaller diameters. Many of these asteroids are an asteroid belt between the orbits of Mars and Jupiter.
Meteoroids, meteors and meteorites are categorized based on which of the following?
their temperature |
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their density |
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their size |
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their location |
Smaller rocks shed by asteroids and comets are called meteoroids. When these rocks reach Earth's atmosphere, they burn up in the mesosphere and become meteors. If a meteor manages to reach the Earth, it is called a meteorite.
Which of the following describes the Earth's mantle?
primarily solid |
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solid |
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primarily liquid |
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liquid |
Mantle makes up 84% of the Earth's volume and has an average thickness of approximately 1,800 miles (2,900 km). It is dense, hot, and primarily solid although in places it behaves more like a viscous fluid as the plates of the upper mantle and crust gradually "float" along its circumference.