A body of mass 1 Kg is acted upon by a variable force. The force varies with the distance covered by the object shown in figure. What is the speed of the body when it is covered 25 minutes? Assume that the body starts from rest.

1. 20 m/s.      2. 30 m/s.   3. 40 m/s   4. 10 m/s

Given,
            Mass = 5 kg
       Distance = 25 m