[填空题]
A particle moves in a straight linow 6lo htt6t*)e and i (sn4.chg/wit ts velocity, $v \mathrm{~ms}^{-1}$ , at time t seconds, is given by $v(t)=\left(t^{2}-2\right)^{2}$ , for $0 \leq t \leq 2$ .
1. Find the initial velocity of the particle.
2. Find the value of t for which the particle is at rest.
3. Find the total distance travelled by the particle in the first 2 seconds.
4. Show that the acceleration of the particle is given by $a(t)=4 t^{3}-8 t$ .
5. Find the values of t for which the velocity is positive and the acceleration is negative. a b =
