<span>C.the railroads had to pass over mountains and rivers</span>
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The term that states that the amount of change in the stimulus necessary to produce such a difference depends on the intensity at which the stimulus is presented is: Difference Threshold.
<h3>What is the Difference Threshold?</h3>
The difference threshold states that is the noticeable difference that can be detected in a stimulus. It describes the minimum change that can be detected half of the time by an observer.
So, the condition described above can be described as the Difference Threshold.
Learn more about the difference threshold here:
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Answer:
Food surpluses affected the people and populations because the availability of surplus food means an individual will most likely have more children. This is because food is needed for survival and having it excess can also help in providing more money and other resources.
Increase in population helped and allowed the ancient civilizations to grow and prosper as a result of the increase in the population helping in different areas of the economy of the country. This caused a ripple effect by increasing trade between countries which also had a positive effect on the civilization process.
