A point P moves in counter-clockwise direction on a circular path as shown in the figure. The movement of P is such that it sweeps out a length s = t3 + 5, where s is in metres and t is in seconds. The radius of the path is 20m. The acceleration of P when t = 2 s is nearly
(a) 14ms–2
(b) 13ms–2
(c) 12ms–2
(d) 7.2ms–2
