Low clouds
Stratus clouds are uniform grayish clouds that often cover the sky. Usually no precipitation falls from stratus clouds, but they may drizzle. When a thick fog “lifts,” the resulting clouds are low stratus. Nimbostratus clouds form a dark gray, “wet” looking cloudy layer associated with continuously falling rain or snow. They often produce light to moderate precipitation.
Middle clouds
Clouds with the prefix “alto” are middle-level clouds that have bases at 6,500 to 23,000 feet up. Altocumulus clouds are made of water droplets and appear as gray, puffy masses, sometimes rolled out in parallel waves or bands. These clouds on a warm, humid summer morning often mean thunderstorms by late afternoon. Altostratus clouds, gray or blue-gray, are made up of ice crystals and water droplets. They usually cover the sky. In thinner areas of them, the sun may be dimly visible as a round disk. Altostratus clouds often form ahead of storms that produce continuous precipitation.
High clouds
Cirrus clouds are thin, wispy clouds blown by high winds into long streamers. They are considered “high clouds,” forming at more than 20,000 feet. They usually move across the sky from west to east and generally mean fair to pleasant weather. Cirrostratus, thin, sheetlike clouds that often cover the sky, are so thin the sun and moon can be seen through them. Cirrocumulus clouds appear as small, rounded white puffs. Small ripples in the cirrocumulus sometimes resemble the scales of a fish, creating what is sometimes called a “mackerel sky.”
Vertical clouds
Cumulus clouds are puffy and can look like floating cotton. The base of each is often flat and may be only 330 feet above ground. The top has rounded towers. When the top resembles a cauliflower head, it is called “cumulus congestus.” These grow upward and if they continue to grow vertically can develop into a giant cumulonimbus, a thunderstorm cloud, with dark bases no more than 1,000 feet above ground and extending to more than 39,000 feet. Tremendous energy is released by condensation of water vapor in a cumulonimbus. Lightning, thunder and violent tornadoes are associated with them.
Answer:
The age of the sample is 4224 years.
Explanation:
Let the age of the sample be t years old.
Initial mass percentage of carbon-14 in an artifact = 100%
Initial mass of carbon-14 in an artifact = ![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
Final mass percentage of carbon-14 in an artifact t years = 60%
Final mass of carbon-14 in an artifact = ![[A]=0.06[A_o]](https://tex.z-dn.net/?f=%5BA%5D%3D0.06%5BA_o%5D)
Half life of the carbon-14 = 
![[A]=[A_o]\times e^{-kt}](https://tex.z-dn.net/?f=%5BA%5D%3D%5BA_o%5D%5Ctimes%20e%5E%7B-kt%7D)
![[A]=[A_o]\times e^{-\frac{0.693}{t_{1/2}}\times t}](https://tex.z-dn.net/?f=%5BA%5D%3D%5BA_o%5D%5Ctimes%20e%5E%7B-%5Cfrac%7B0.693%7D%7Bt_%7B1%2F2%7D%7D%5Ctimes%20t%7D)
![0.60[A_o]=[A_o]\times e^{-\frac{0.693}{5730 year}\times t}](https://tex.z-dn.net/?f=0.60%5BA_o%5D%3D%5BA_o%5D%5Ctimes%20e%5E%7B-%5Cfrac%7B0.693%7D%7B5730%20year%7D%5Ctimes%20t%7D)
Solving for t:
t = 4223.71 years ≈ 4224 years
The age of the sample is 4224 years.
True.
Dementia's main cause is Alzheimer's disease (50%-70% of cases). You can find it in the DSM-5 as Major Neurocognitive Disorder due to Alzheimer's Disease.
Explanation:
Because a large amount of energy is required to break the strong inter-ionic attraction.
CaS => Ca2+ & S2-
Answer:
Bohr thought that electrons orbited the nucleus in circular paths; whereas in the modern view atomic electron structure is more like 3D standing waves. Bohr built upon Rutherford's model of the atom. ... He believed that electrons moved around the nucleus in circular orbits with quantised potential and kinetic energies.
Explanation:
