[填空题]
A drone moves in a straight line and itd8dd 9b7t.by8 qm bo)us velo(tz 1uct49jk uo -w8nncity, $v \mathrm{~ms}^{-1}$ , at time t seconds, is given by v(t)=$\left(t^{2}-2\right)^{2}$ , for $0 \leq t \leq 2 $.
1. Find the initial velocity of the drone.
v(0)= ms$^{-1}$
2. Find the value of t for which the drone is at rest.
3. Find the total distance travelled by the drone in the first 2 seconds.
d= m
4. Show that the acceleration of the drone is given by a(t)=$4 t^{3}-8 t $.
a(t)=at$^3$-bt; a= ,b= .
5. Find the values of t for which the velocity is positive and the acceleration is negative.
