Answer:
The current amount of the Potassium-40 sample is approximately 37.521 grams.
Explanation:
The amount of the sample of the radioactive isotope decays exponentially in time, the amount of mass of the sample as a function of time (
), in grams, is described below:
(1)
Where:
- Initial mass, in grams.
- Time, in years.
- Time constant, in years.
The time constant can be found from half life (
), in years, described in statement:
(2)
If we know that 
, 
and 
, then the current amount of the sample is:
The current amount of the Potassium-40 sample is approximately 37.521 grams.
Answer:
B. Nation
Explanation:
B is the best answer here because culture, nationality, history, and ethnicity are all directly tied to one's country (nation). Territory and boundary are not as specific, and state is too narrow.
Answer:
the 9 percent claim is demonstrably false on a number of levels. First, the entire brain is active all the time. The brain is an organ. Its living neurons, and the cells that support them, are always doing something. (Where’s the “you only use 9 percent of your spleen” myth?) Joe LeDoux, a professor of neuroscience and psychology at NYU, thinks that people today may be thrown off by the “blobs”—the dispersed markers of high brain activity—seen in functional magnetic resonance imaging (fMRI) of the human brain. These blobs are often what people are talking about when they refer to the brain “lighting up.”
Say you’re watching a movie in an fMRI scanner. Certain areas of your brain—the auditory and visual cortices, for instance—will be significantly more active than others; and that activity will show up as colored splotches when the fMRI images are later analyzed. These blobs of significant activity usually cover small portions of the brain image, often less than 10 percent, which could make it seem, to the casual observer, that the rest of the brain is idling. But, as LeDoux put it to me in an email, “the brain could be one hundred percent active during a task with only a small percentage of brain activity unique to the task.” This kind of imaging highlights big differences in regional brain activity, not everything the brain is doing.
In fact, the entire premise of only “using” a certain proportion of your brain is misguided. When your brain works on a problem—turning light that hits your retina into an image, or preparing to reach for a pint of beer, or solving an algebra problem—its effectiveness is as much a question of “where” and “when” as it is of “how much.” Certain regions of the brain are more specialized than others to deal with certain tasks, and most behavior depends on tight temporal coordination between those regions. Your visual system helps you locate that pint of beer, and your motor system gets your hand around it. The idea that swaths of the brain are stagnant pudding while one section does all the work is silly. The brain is a complex, constantly multi-tasking network of tissue.
Explanation:
Answer:
place, space, and scale
Explanation:
A geographer investigate issues from the view point of location according to place, space and the scale.
The place is an element of location that describes the position or the domain of occurrence of issue.
Space refers the area occupied by a body or the area where an issue is domiciled.
The scale refers to the magnitude at which an issue is view or observed.
Geographers tends to synthesize and combine these different lenses to observe and investigate an issue. Almost everything on earth can be correlated spatially using these lenses.
Their homes will likely be crushed by another lahar.These dangers incorporate surges, lahars, avalanches, pyroclastic streams, magma streams, and tephra aftermath. These perils can devastate a region as well as impact water quality and other wellbeing dangers in spots that survive. Some of Mount Rainier's risks are not related with an ejection.
