Yes, they are the same rivers. The Zaire River is sometimes called the Congo River, because part of it is in the Congo.
No
the Congo river is located in the central region of Africa
Right Continent, wrong River, the Nile is the longest river. The Congo River is the second largest in Africa, and 8th overall in the World.
According to some scientists it is, but there is no confimation yet of this research.