A particle moves in xy plane. The position vector at any time t is r = {(2t)I + (2t²)j} m. The rate of change of θ at time t=2 second (where θ is an angle which its velocity vector makes with positive x−axis) is:
A. 2/17 rad/s
B. 1/14 rad/s
C. 4/7 rad/s
D. 6/5 rad/s