| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.44 |
| Score | 0% | 69% |
Convert -20C° to F°.
-36 |
|
-4 |
|
78 |
|
36 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(-20) + 32\)
\(F° = {-180 \over 5} + 32\)
\(F° = -36 + 32 = -4\)
The pitch of the siren of an approaching ambulance changes as it approaches you. This is an example of which of the following?
Doppler effect |
|
sound radiation |
|
refraction |
|
reflection |
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.
This skeletal system is common in arthropods like insects, spiders, and crustaceans.
vertebrate |
|
exoskeleton |
|
endoskeleton |
|
bone |
An exoskeleton (external skeleton) is common in arthropods like insects, spiders, and crustaceans.
Reproductive haploids are also known as:
sperm |
|
ovum |
|
gametes |
|
diploids |
Reproductive (haploid) cells known as gametes have half as many (23) pairs of chromosomes as normal (diploid) cells. When the male gamete (sperm) combines with the female gamete (ovum) through meiosis to form a zygote, each gamete supplies half the chromosomes needed to form the normal diploid cells.
Which of the following is sedimentary rock?
obsidian |
|
basalt |
|
slate |
|
sandstone |
The Earth's rocks fall into three categories based on how they're formed. Igneous rock (granite, basalt, obsidian) is formed from the hardening of molten rock (lava), sedimentary rock (shale, sandstone, coal) is formed by the gradual despositing and cementing of rock and other debris, and metamorphic rock (marble, slate, quartzite) which is formed when existing rock is altered though pressure, temperature, or chemical processes.