What types of obstacles do historians have to overcome to give a straightforward account of past events?

Evidences

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Explanation:

Evidence, the function of the historian is to show, interpret and give the clarity necessary to tell the story with real and confirmed facts and this generates a great difficulty, because many times the information was lost in the course of time, the information is ambiguous and manipulated That is why you must carry out an excellent investigation.

popular themes. Historical importance, this is a very important issue, since if it is a fact with little importance the sources of information and research support will not have a social significance

they died because of a disease during the first spanish colonies.

in the 1800s, locomotives powered by steam made transportation faster and cheaper. the resulting rapid growth of railroads led to the connection of the atlantic and pacific railroad in oklahoma city in 1897.

in the last years of the century, the improvement of steam-based engines the expansion and growth of railroads. this growth increased when the companies started to build and expand, such as the atlantic and pacific railroad, which connected new mexico with california, and missouri with oklahoma. many of these new networks were built in oklahoma, and these changes transportation henceforward.