A particle A moves in a straight line with constant speed 10 m s^-1. Two seconds after A passes a point O on the line, a particle B passes through O, moving along the line in the same direction as A. Particle B has speed 16 m s^-1 at O and has a constant deceleration of 2 m s^-2.

(i) Find expressions, in terms of t, for the displacement from O of each particle t s after B passes through O.

(ii) Find the distance between the particles when B comes to instantaneous rest.

(iii) Find the minimum distance between the particles.