Explanation: Most of these ranges are separated from each other by numerous small rivers. The Barak is an important river in Manipur and Mizoram.

• The physiography of Manipur is unique by the presence of a large lake known as ‘Loktak’ lake at the centre, surrounded by mountains from all sides.
• Mizoram which is also known as the ‘Molassis basin’ which is made up of soft unconsolidated deposits. Most of the rivers in Nagaland form the tributary of the Brahmaputra.
• While two rivers of Mizoram and Manipur are the tributaries of the Barak river, which in turn is the tributary of Meghna; the rivers in the eastern part of Manipur are the tributaries of Chindwin, which in turn is a tributary of the Irrawady of Myanmar.

Source: Class 11th NCERT