The correct answer is - d. colder and denser.
The main differences between the surface currents and deeper currents are the temperature and density, and that actually decides their position in the water, on the surface, or deeper.
The surface currents are warmer, and because they are warmer the molecules are much more loose, so the density is lower, which in return makes it easier, thus it is in the surface.
The deeper currents are colder, and because they are colder the molecules are much closer and more concentrated, so the density is higher, which means that they are heavier, thus fall deeper below the easier currents.
Answer:
B. During warmer climates, glaciers melt and sea level rises.
The correct answer should be Census
Answer:
2000m
Explanation:
Given parameters:
Rate of regional erosion = 2 m per 1000years
Unknown:
Amount of regional erosion in 1, 000, 000 years.
Solution:
If it takes 1000 years for regional erosion to remove 2m of earth
then, in 1, 000, 000 years, the amount of regional erosion will be: 
⇒ 2000m
In a million years to come, 2000m of earth would have been eroded as a result of regional erosion.
