Before Champaran Satyagraha, the farmers of Champaran used to follow the 'Panchkathiya' system, whereby five katthas of land in a bigha had to be planted with ___.
Due to an acceleration of 1 m/s2 the velocity of a body increases from 15 m/s to 20 m/s in a certain period. Find the displacement (in m) of the body in that period.