Which describes a major challenge facing the building of the transcontinental railroad

Brainliesttt asap!me : ) answer in your own words. what was the relationship between medieval theories about scientific reasoning and the kind of reasoning favored during the scientific revolution?

How did the first punic war differ from the second punic war

"but let us admit texas, and we shall place the balance of power in the hands of the texans themselves. they, with the southern states, will control the policy and the destiny of this nation; our tariff will then be held at the will of the texan advocates of free trade. are our friends of the north prepared to deliver over this great national policy to the people of texas? " - rep. joshua giddings, ohio, may 21, 1844 this quote points to what major issue in the years leading up to the civil war?