The displacement of a particle from a fixed origin after t t\,t seconds is x=t2(t−k)x=t^2(t-k)x=t2(t−k) metres, where k k\,k is a positive constant. The particle is instantaneously at rest when t=4t=4t=4.
Find kkk.
Find the total distance travelled during the first 6 seconds.
Find the acceleration when t=6t=6t=6.