Answer:
1. Economic
2. It was where the roman empire began
Step-by-step explanation:
"Eastern Empire had a more established urban culture and greater financial resources (given the gold mines in Thrace and near Constantinople) compared to the West, thereby allowing the Imperial government in Constantinople more leeway in trying to maintain control, and also in paying off barbarians to avoid the problems that would beset the financially destitute West.
Combined with a lack of mass Germanic migration into their territories, the Eastern Roman Empire was thus in a much better position to survive the collapse of the Empire."