<span>The threat to internal validity is the Mortality. Internal
validity is the measure in which the causality of the stimuli studied
is analyzed, that is, if the results of the study are due to the
interaction of the variables analyzed or are due to the interaction with
other variables. <span>Mortality is an error that occurs if the
conclusions of the study are made only on the basis of the participants
who were from beginning to end in the investigation, without taking into
account those who left the study.
I hope my answer can help you.
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The best way to handle this situation is to tell to the guest who is in a hurry that you won't be able to take his request as the top priority because there are others who are first in line before him. It would be best to advice him that his order would still be taken care of and would do it as fast as it can with trying to explain that he's not the only one in the restaurant to assure him and prevent conflict.
Answer:
A they used stone tools and used art to express themselves
The Reconstruction era is always a challenge to teach. First, it was a period of tremendous political complexity and far-reaching consequences. A cursory survey of Reconstruction is never satisfying, but a fuller treatment of Reconstruction can be like quick sand—easy to get into but impossible to get out of. Second, to the extent that students may have any preconceptions about Reconstruction, they are often an obstacle to a deeper understanding of the period. Given these challenges, I have gradually settled on an approach to the period that avoids much of the complex chronology of the era and instead focuses on the “big questions” of Reconstruction.
However important a command of the chronology of Reconstruction may be, it is equally important that students understand that Reconstruction was a period when American waged a sustained debate over who was an American, what rights should all Americans enjoy, and what rights would only some Americans possess. In short, Americans engaged in a strenuous debate about the nature of freedom and equality.
With the surrender of Confederate armies and the capture of Jefferson Davis in the spring of 1865, pressing questions demanded immediate answers.
