| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.00 |
| Score | 0% | 60% |
Which of these is matter than cannot be separated into different types of matter by ordinary chemical methods?
atom |
|
element |
|
compound |
|
molecule |
An element is matter than cannot be separated into different types of matter by ordinary chemical methods.
The pitch of the siren of an approaching ambulance changes as it approaches you. This is an example of which of the following?
sound radiation |
|
refraction |
|
reflection |
|
Doppler effect |
The Doppler effect occurs when the source or listener (or both) of sound waves is moving. If they're moving closer together, the listener perceives the sound with a higher pitch and, when they're moving apart, the listener perceives the sound with a lower pitch.
Veins __________ blood at __________ pressure.
oxygenated, low |
|
deoxygenated, low |
|
oxygenated, high |
|
deoxygenated, high |
Veins carry blood back to the heart from the body. While arteries are thick-walled because they carry oxygenated blood at high pressure, veins are comparatively thin-walled as they carry low-pressure deoxygenated blood. Like the heart, veins contain valves to prevent blood backflow.
212°F is how many °C?
\(135 {5 \over 9}\) |
|
100 |
|
0 |
|
-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 cell biology, cytokinesis results in two separate:
cells |
|
chromatids |
|
nuclei |
|
chromosomes |
During cell division, the cytokinesis phase occurs when cytoplasm and cell membranes complete their separation resulting in two separate cells.