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:
If the contour lines are close together it means that the change in elevation is very steep.
Explanation:
A is not correct because if the topography is almost flat, the contour lines would be very far apart.
B is correct because the closer the contour lines are, the steeper the topography is, meaning that the terrain is very steep.
C is not correct because if the elevation is not changing, the contour lines will be missing from that part of the map.
Answer:
Cylindrical map projections
Explanation:
Cylindrical map projections are used for portraying the Earth. Cylindrical map projections are rectangles, but are called cylindrical because they can be rolled up and their edges mapped in a tube, or cylinder. They have straight coordinate lines with horizontal parallels crossing meridians at right angles. All meridians are equally spaced and the scale is consistent along each parallel. The only factor that distinguishes different cylindrical map projections from one another is the scale used when spacing the parallel lines on the map.
Cylindrical map projections are great for comparing latitudes to each other and are useful for teaching and visualizing the world as a whole, by determining continents, languages, etc but really aren’t the most accurate way of visualizing how the world really looks in its entirety.
Answer: B
Explanation:
The answer to the question is Australia. It is in the southeast region of the Earth. It is the largest country in Oceania. It is the answer to the question.
