River valley trade made them key economic areas.
Hope this helped. :)
did you ever find out the answer
The difference between the two mentioned magnitudes is 4.
A magnitude 1 earth-quack is 10000 times bigger than a magnitude -3 earth-quack. On the other hand, it is 1000000 times stronger in terms of energy release.
Note: To calculate the difference in energy between two earth-quacks, first you calculate the difference between their magnitudes and then you raise 10 to the output you obtain.
A stem-and-leaf graph is a way to organize a large number of data
