| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.95 |
| Score | 0% | 59% |
212°F is how many °C?
100 |
|
0 |
|
\(135 {5 \over 9}\) |
|
-100 |
The formula to convert from F° to C° is:
\(C° = {5 \over 9} (F° - 32)\)
plugging in our values gives:
\(C° = {5 \over 9} (212 - 32)\)
\(C° = {5 \over 9} (180) = {{180 \times 5} \over 9}\)
\(C° = {900 \over 9}\)
\(C° = 100\)
In the heart, blood flows from the right __________ to the lungs then back to the heart via the left __________.
ventricle, atrium |
|
atrium, atrium |
|
atrium, ventricle |
|
ventricle, ventricle |
The two largest veins in the body, the venae cavae, pass blood to the right ventricle which pumps the blood to the lungs through the pulmonary artery. Blood picks up oxygen in the lungs and returns it to the left atrium via the pulmonary vein.
Which of the following describes the Earth's mantle?
primarily liquid |
|
solid |
|
primarily solid |
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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.
Which of the following substances gives up negatively charged hydroxide ions (OH-) when dissolved in water?
ion |
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acid |
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hydrogen |
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base |
An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.
The ozone layer is in which of Earth's atmospheric layers?
stratosphere |
|
mesosphere |
|
thermosphere |
|
troposphere |
The stratosphere is just above the troposphere and is stratified in temperature with warmer layers higher and cooler layers closer to Earth. This increase in temperature is a result of absorption of the Sun's radiation by the ozone layer.