Application of differentiation

The motion of a particle moving along the x-axis is described by x = t^3 - 6t^2 + 9t + 5, where x m is the displacement at time t seconds after start.

(a) Find the magnitude and the direction of the initial velocity and initial acceleration of the particle.
(b) Find the interval of the value of t in which the particle is moving towards the origin.
(c) Find the acceleration of the particle when the particle changes its direction of motion.
(d) Find the total distance travelled by the particle in the first 5 minutes.