| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.61 |
| Score | 0% | 72% |
Which of blood component fights infection?
white blood cells |
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plasma |
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platelets |
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red blood cells |
Blood is created in bone marrow and is made up of cells suspended in liquid plasma. Red blood cells carry oxygen, white blood cells fight infection, and platelets are cell fragments that allow blood to clot.
Which of these is a type of Earth's crust?
metamorphic |
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terrestrial |
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sedimentary |
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oceanic |
The crust is the Earth's outermost layer and is divided into oceanic and continental types. Oceanic crust is 3 miles (5 km) to 6 miles (10 km) thick and is composed primarily of denser rock. Continental crust is 20 to 30 miles (30 to 50 km) thick and composed primarily of less dense rock. The crust makes up approximately one percent of the Earth's total volume.
The formula for acceleration is which of the following?
\(\vec{a} = { m \over \vec{F} }\) |
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\(\vec{a} = { m \over F }\) |
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\(\vec{a} = { \vec{F} \over m }\) |
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\(\vec{a} = \vec{F} m\) |
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, \(\vec{F} = m\vec{a}\).
A human heart consists of how many chambers?
2 |
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4 |
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1 |
|
8 |
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.
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:
\(C° = {5 \over 9} (212 - 32)\)
\(C° = {5 \over 9} (180) = {{180 \times 5} \over 9}\)
\(C° = {900 \over 9}\)
\(C° = 100\)