Greenhouse effect, Latitude, heat transport in the biosphere.
Around 1800 (plus or minus about 5 years) is when it was estimated that the world's population had reached 1 billion.
The correct answer is - dunes.
The dunes, or sand dunes, are a relief forms that are formed by deposition of material. In the process of forming a dune, the responsibility goes to the eolian processes (wind processes). The wind has its own mechanical power to erode the rocks, but it also has the power to transport the material. The stronger the wind, the bigger the particles it can transport, and vice versa. When the wind is transporting a certain material, in the case of the dunes it will be sand particles, eventually it will start to lose on speed, and as it loses on speed, it loses on power, so the sand particles are starting to fall on the ground and deposit. s more and more sand particles are depositing, the dune starts to form, and it is growing bigger as more sand particles are falling on it.
The correct answer is A. Tierra Fria.
Tierra Fria is composed of highlands, but even though it is very high area, because of the low latitude and high altitude, this area has a very pleasant climate which is actually pretty similar to the oceanic coastal regions of the temperate climates. Because of this, it is very suitable for the livestock, since the weather conditions are very nice, the grass is green for most of the year and it is in abundance, plus the region is clean, and also lacks predators.
