| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.03 |
| Score | 0% | 61% |
An endoskeleton (internal skeleton) is a charateristic of __________ animals, including humans.
sentient |
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spiny |
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vertebrate |
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arthropod |
An endoskeleton (internal skeleton) is a charateristic of vertebrate animals, including humans.
Convert -20C° to F°.
-4 |
|
36 |
|
78 |
|
-36 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(-20) + 32\)
\(F° = {-180 \over 5} + 32\)
\(F° = -36 + 32 = -4\)
Which of the following substances gives up positively charged hydrogen ions (H+) when dissolved in water?
base |
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solution |
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alkaline |
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acid |
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.
-40°F is how many °C?
-40 |
|
\(-{40 \over 9}\) |
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\({40 \over 9}\) |
|
-8 |
The formula to convert from F° to C° is:
\(C° = {5 \over 9} (F° - 32)\)
plugging in our values gives:
\(C° = {5 \over 9} (-40 - 32)\)
\(C° = {5 \over 9} (-72) = {{-72 \times 5} \over 9}\)
\(C° = {-360 \over 9}\)
\(C° = -40\)
Acceleration is the rate of change of velocity per unit of time. Which of these is the formula for acceleration?
\(\vec{a} = { \Delta \vec{v} \over t }\) |
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\(\vec{a} = { \vec{v} \over t }\) |
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\(\vec{a} = \Delta \vec{v} t \) |
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\(\vec{a} = { t \over \Delta \vec{v} }\) |
Acceleration is the rate of change of velocity per unit of time. In physics, the delta symbol (\(\Delta\)) represents change so the formula for acceleration becomes \(\vec{a} = { \Delta \vec{v} \over t }\)