Answer: Scientists have recorded five significant ice ages throughout the Earth's history: the Huronian (2.4-2.1 billion years ago), Cryogenian (850-635 million years ago), Andean-Saharan (460-430 mya), Karoo (360-260 mya) and Quaternary (2.6 mya-present).
The last option is the answer
The answer is B. Because this was their transport to get round coastlines and down rivers.
First was the Roman Republic, then came the Roman Empire. In the 4th century BCE, the Roman Republic turned to imperialism. After losing a significant battle with the Gauls, a Celtic people, the Romans concluded that in order to sustain safety, they would have to expand their territory so the frontiers would be a good distance from the capital, Rome. They successfully fought a series of wars with other Italian city-states as well as the Carthaginians, achieving their goal. Warfare gave excessive power to the military leaders, weakening the influence of the Senate and thus the democracy became undermined. That is how it was transformed to a vast empire.
During the 1800s, the economy of the united states was considered small and still developing, largely agricultural. This provoked the capitalist to begin working through the Laizes Faire method in the attempt to alleviate the status of the economy. The answer would have to be capitalism.