| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.30 |
| Score | 0% | 66% |
What prevents blood pumped out of the ventricles from flowing back into the heart?
atria |
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platelets |
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valves |
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capillaries |
The heart is the organ that drives the circulatory system. In humans, it consists of four chambers with two that collect blood called atria and two that pump blood called ventricles. The heart's valves prevent blood pumped out of the ventricles from flowing back into the heart.
Meteoroids, meteors and meteorites are categorized based on which of the following?
their size |
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their location |
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their temperature |
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their density |
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 is the formula for power?
\(P = {w \over t}\) |
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\(P = w t\) |
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\(P = \vec{w}t\) |
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\(P = {\vec{w} \over t}\) |
Power is the rate at which work is performed or work per unit time: \(P = {w \over t}\) and is measured in watts (W).
Which of these is not a type of fat?
monounsaturated |
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cholesterol |
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saturated |
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polyunsaturated |
Fats come in three types, saturated (meats, shellfish, eggs, milk), monounsaturated (olives, almonds, avocados), and polyunsaturated (vegetable oils).
50°F is how many °C?
122 |
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10 |
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-10 |
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58 |
The formula to convert from F° to C° is:
\(C° = {5 \over 9} (F° - 32)\)
plugging in our values gives:
\(C° = {5 \over 9} (50 - 32)\)
\(C° = {5 \over 9} (18)\)
\(C° = {90 \over 9}\)
\(C° = 10\)