What, in addition to geographic boundaries, might have kept the people of the huang river civilization from traveling to far-distant regions?

they feared that their bronze weapons would be no match for the iron weapons of ancient egypt.
they could get everything locally that they needed to survive and grow.
they had learned about the other river valley civilizations but feared contact would bring invasion.
they had not yet developed a system of money based on coins.

Need plz? due in 10 will give brainliest which of the following was the most significant aspect of revel's election to the senate? a.his election showed that the u.s. would quickly move past the civil war. b.his election to uphold the thirteenth and fourteenth amendments which gave freed slaves citizenship and voting rights. c.his election demonstrated the states were united in a union once more. d.his election was the first step in opening doors for other african-american political leaders.

In which two days did the spread of enlightenment thought contribute to the french revolution

How does the battle of midway illustrate the importance of intelligence gathering and espionage in modern warfare?