<span>C.the railroads had to pass over mountains and rivers</span>
1. Many sacrifices will be made as it will be necessary for me to stay away from my family and friends, which may be a little lonely for the duration of the research. It may also be necessary for me to live in a place that is not very comfortable and has fewer resources that I am used to. It may be that the place where the research will be carried out has a very different geography and climate from the place where I live, which may generate even more discomforts for me, such as very high or very low temperatures.
2. Ideally, I should take few personal belongings, so I don't have to spend a lot of time managing them and focus my time on doing the research. However, my management must be around the most necessary personal items, which I could not live without.
3. This will depend on the research and what it is evaluating, but I can guarantee that computers and organizational systems will be needed through spreadsheets and software that remain the tabulation of the collected data, their storage and optimization.
Answer: Trade allowed new technologies to spread.
Explanation:
