Wind, different air pressure.
The correct answer is - B. large empires developed.
The mountains are a natural barrier for lot of human activities, and one of those is the formation of settlements, big countries, or empires. The creation of large empires on a mountainous terrain is extremely hard and unpractical, and there's very few cases in the human history that that has been performed well. The reasons for that is that in the mountainous regions it is hard to create a network of roads, build large settlements, and also there's lack of natural resources and food, so the people had the tendency to create small settlements, or city-states in this kind of circumstances.
Oil shale<span> is a type of </span>sedimentary rock<span> that is rich in kerogen. </span>Kerogen<span> is a part of rock that breaks down and releases hydrocarbons when heated. </span>Hydrocarbon<span>s are substances made entirely of hydrogen and carbon. </span>Petroleum<span> and </span>natural gas<span> are probably the most familiar hydrocarbons. The hydrocarbons in oil shale can be used as an alternative to petroleum or natural gas.</span>
The Andromeda Galaxy is 2.5 Million Light Years away from the Milky Way Galaxy.
Most Yemenis' lives have been ruined by the lengthy and destructive conflict that began in March 2015. A wrecked economy, widespread unemployment, and unpaid wages have decimated incomes and forced many into debt.
