a,
Sau $\Delta t=3(s)$ đạt vận tốc $v=0$
Gia tốc:
$a=\dfrac{\Delta v}{\Delta t}=\dfrac{0-2}{3}=\dfrac{-2}{3}(m/s^2)$
b,
$v=v_o+at\Rightarrow v=2-\dfrac{2}{3}.1=\dfrac{4}{3}(m/s)$
c,
$v^2-v_o^2=2as$
$\Leftrightarrow s=\dfrac{-2^2}{2.\dfrac{-2}{3}}=3(m)$