Point P moves along the z-axis in such a way that its position at time t/s is given by

x = 2t³-15t² +24t ft i. Find the velocity and acceleration of P at time t ii. In which direction and how fast is P moving at t = 2s? Is it speeding up or slowing down at that time? iii. When is P instantaneously at rest? When is its speed instantaneously not changing ?