I do not think so. what other technology could we use.
I would put eater and transportation.
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.
The answer is rainforests. The destruction of rainforests can lead to global warming due to the accumulation of carbon dioxide as a greenhouse gas in the atmosphere. This is because rainforests are major carbon sinks because they sequester carbon dioxide from the atmosphere. One of the major rainforests that are facing the threat of human activities is the Amazon and Congo forests.
The answer is south america’s location atop the Nazca and South American plates of the circum-pacific belt. The circum-pacific belt is also known as the ‘ring of fire’ because there is a subduction zone in the region. The Cocos plate is subducting under the Caribbean Plate. This creates friction between the two plates with occasional release of high amounts of energies when a stuck region gets unstuck abruptly. This region accounts for approximately 90% of the world’s earthquakes.
Answer: As altitude increases, atmospheric pressure decreases
Explanation:
Atmospheric pressure 
is defined as the force 
per unit area 
the air that forms the atmosphere exerts on the Earth's surface:
It should be noted that as the altitude increases less air is above and, therefore the air weights less. This is because the atmosphere losses density as we ascend, causing less air.
However, it is important to point out this decrease in pressure is not linear, since at the beginning (in the first kilometers above sea level) it reduces more rapidly than in the next kilometers above. That is why this relationship between atmospheric pressure and altitude is exponential.
