[问答题]
A particle P starts from a
j 0y u cmf sg,2zs1-trpu57w/z poin
)hzc6avmw 2ey ofc zn(f:/j6(t O and moves along a horizontal straight line. Its
wz:j(f ohec6vanmc)y2 f( z /6velocity$ v \mathrm{~ms}^{-1}$ after t seconds is given by
The following diagram shows the graph of v .
1. Find the initial velocity of particle P .
2. Find the acceleration of the particle in the first second.
3. How many times does the particle change direction in the first 8 seconds. Explain your answer.
4. Find the total distance travelled by the particle in the first 8 seconds.
