| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.42 |
| Score | 0% | 68% |
Which of the following describes the Earth's mantle?
solid |
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primarily 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.
The formula for acceleration is which of the following?
\(\vec{a} = \vec{F} m\) |
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\(\vec{a} = { m \over F }\) |
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\(\vec{a} = { \vec{F} \over m }\) |
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\(\vec{a} = { m \over \vec{F} }\) |
Newton's second law of motion leads to the formula for acceleration which is a measure of the rate of change of velocity per unit time and, if you solve for positive acceleration, reveals how much net force is needed to overcome an object's mass. The formula for acceleration is \(\vec{a} = { \vec{F} \over m }\) or, solving for force, \(\vec{F} = m\vec{a}\).
50°F is how many °C?
58 |
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10 |
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122 |
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-10 |
The formula to convert from F° to C° is:
\(C° = {5 \over 9} (F° - 32)\)
plugging in our values gives:
\(C° = {5 \over 9} (50 - 32)\)
\(C° = {5 \over 9} (18)\)
\(C° = {90 \over 9}\)
\(C° = 10\)
In the food chain, bacteria and fungi convert the organic matter in the dead bodies of plants and animals into simple nutrients. Bacteria and fungi are:
primary consumers |
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scavengers |
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producers |
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decomposers |
Decomposers (saprotrophs) are organisms such as bacteria and fungi that break down the organic matter in the dead bodies of plants and animals into simple nutrients.
The four planets closest to the Sun are called terrestrial. What does terrestrial mean?
the planets have water |
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the planets have moons |
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the planets are Earth-like |
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the planets have magnetic fields |
The four planets closest to the Sun (Mercury, Venus, Earth, and Mars) are called terrestrial (Earth-like) planets because, like the Earth, they're solid with inner metal cores covered by rocky surfaces.