Answer:
The first occurrence (chronologically) was
Regional kingdoms began to replace most of the city-states of the northern region of Harappan Society.
Explanation:
Of all that are stated in the question, Regional kingdoms began to replace most of the city-states of the northern region of Harappan Society first occured
Around 4,350 years ago, many factors responsible for migration led people to abandon their settlements and migrate to southern and eastern regions of India, according to a study by Indian Institute of Technology Kharagpur.
This is also known as Indus valley civilization
In general, the railroads had a positive impact on the relationship between eastern cities and the Great Plains, since they allowed for the transportation of people and goods between these two areas in ways that were far quicker and more efficient than before.
Depending on the source, i would say at least a 2 to 1
Tenth Amendment to the U.S. Constitution "The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people." FEDERALISM
