The velocity of a particle moving along the x axis is given for t > 0 by vx = (32.0t - 2.00t3) m/s, where t is in s. What is the acceleration of the particle when (after t = 0) it achieves its maximum displacement in the positive x direction?
1) -64.0 m/s2
2) zero
3) 128 m/s2
4) 32.0 m/s2
5) -32.0 m/s2
Answer: 1