The "he" here is Constantine the Great, and he moved the capital of the Roman Empire to the city named Constantinopole, previously Byzantium, which today is known as Istanbul, Turkey's biggest city.
-15e+7-5e-9
For get about the - sign and add the 15 and 5
Then place the -sign back
Add 7 to the -9
-20e-2
It would best describe them as politically unstable
no its the practice of drawing maps