Consider the following statements

I. The river Ravi has its source in Kullu district hills near the Rohtang pass.

II. It drains the area between the Pir Panjal and the Dhaula Dhar ranges.

III. It enters the plains of Punjab near Madhopur.

IV. The river roughly marks the boundary between East Punjab and West Punjab.

Which of the statements given above are correct about the river Ravi?